Techniques for handling overlapping sets of downlink control channel resources

ABSTRACT

Techniques for monitoring for control information in sets of downlink control channel resources are described, where multiple sets of downlink control channel resources may overlap. The described techniques include monitoring for one or more search spaces in a set of downlink control channel resources by rate matching downlink control channel resources independently of other sets of downlink control channel resources. Alternatively, overlapping sets of downlink control channel resources may be rate-matched accounting for reference signals of overlapping sets of downlink control channel resources.

CROSS REFERENCE

The present Application for Patent claims priority to U.S. ProvisionalPatent Application No. 62/480,995 by Lee, et al., entitled “TechniquesFor Handling Overlapping Sets of Downlink Control Channel Resources,”filed Apr. 3, 2017, which is assigned to the assignee hereof andincorporated by reference herein.

BACKGROUND Field of the Disclosure

The present disclosure relates to wireless communication systems, andmore particularly to techniques for handling overlapping sets ofdownlink control channel resources such as overlapping downlink controlresource sets or overlapping search spaces.

Description of Related Art

Wireless communication systems are widely deployed to provide varioustypes of communication content such as voice, video, packet data,messaging, broadcast, and so on. These systems may be multiple-accesssystems capable of supporting communication with multiple users bysharing the available system resources (e.g., time, frequency, andpower). Examples of such multiple-access systems include code-divisionmultiple access (CDMA) systems, time-division multiple access (TDMA)systems, frequency-division multiple access (FDMA) systems, andorthogonal frequency-division multiple access (OFDMA) systems.

A wireless multiple-access communication system may include a number ofbase stations, each simultaneously supporting communication for multiplecommunication devices, otherwise known as UEs. In a Long-Term Evolution(LTE) or LTE-Advanced (LTE-A) network, a set of one or more basestations may define an eNodeB (eNB). In a next generation, new radio(NR), millimeter wave (mmW), or 5G network, a base station may take theform of a smart radio head (or radio head (RH)) or access nodecontroller (ANC), with a set of smart radio heads in communication withan ANC defining a gNodeB (gNB). A base station may communicate with aset of UEs on downlink channels (e.g., for transmissions from a basestation to a UE) and uplink channels (e.g., for transmissions from a UEto a base station).

At times, a base station may transmit a downlink control channel to aUE. The downlink control channel may be transmitted to the UE on adownlink control resource set, and in some cases may be transmitted tothe UE in a search space of the downlink control resource set. Thesearch space may include all or a subset of the resources of thedownlink control resource set. The downlink control channel may betransmitted on all or a subset of the resources of the downlink controlresource set and/or all or a subset of the resources of the searchspace.

SUMMARY

Techniques are described for handling overlapping downlink controlresource sets and search spaces. Some of the techniques enable a basestation or UE to determine what signals may be transmitted/received inan overlap in resources between downlink control resource sets and/orsearch spaces. For example, some techniques enable a base station or UEto determine whether a downlink control channel and/or associatedreference signals for the downlink control channel may betransmitted/received within the overlap. Other techniques enable a basestation or UE to determine how a downlink control channel is ratematched around reference signals associated with other downlink controlresource sets, search spaces, or other physical channels within theoverlap.

A method of wireless communication at a user equipment (UE) isdescribed. The method may include identifying a first control resourceset and a second control resource set, wherein resources of the firstcontrol resource set at least partially overlap with resources of thesecond control resource set, monitoring a first search space of thefirst control resource set, wherein the monitoring the first searchspace comprises rate-matching first downlink control channel resourcesof the first control resource set for the first search spaceindependently of the second control resource set, monitoring a secondsearch space of the second control resource set, wherein the monitoringthe second search space comprises rate-matching second downlink controlchannel resources of the second control resource set for the secondsearch space independently of the first control resource set, andcommunicating with a base station based at least in part on controlinformation identified as a result of the monitoring of the first searchspace or the monitoring of the second search space.

An apparatus for wireless communication is described. The apparatus mayinclude means for identifying a first control resource set and a secondcontrol resource set, wherein resources of the first control resourceset at least partially overlap with resources of the second controlresource set, means for monitoring a first search space of the firstcontrol resource set, wherein the monitoring the first search spacecomprises rate-matching first downlink control channel resources of thefirst control resource set for the first search space independently ofthe second control resource set, means for monitoring a second searchspace of the second control resource set, wherein the monitoring thesecond search space comprises rate-matching second downlink controlchannel resources of the second control resource set for the secondsearch space independently of the first control resource set, and meansfor communicating with a base station based at least in part on controlinformation identified as a result of the monitoring of the first searchspace or the monitoring of the second search space.

Another apparatus for wireless communication is described. The apparatusmay include a processor, memory in electronic communication with theprocessor, and instructions stored in the memory. The instructions maybe operable to cause the processor to identify a first control resourceset and a second control resource set, wherein resources of the firstcontrol resource set at least partially overlap with resources of thesecond control resource set, monitor a first search space of the firstcontrol resource set, wherein the monitoring the first search spacecomprises rate-matching first downlink control channel resources of thefirst control resource set for the first search space independently ofthe second control resource set, monitor a second search space of thesecond control resource set, wherein the monitoring the second searchspace comprises rate-matching second downlink control channel resourcesof the second control resource set for the second search spaceindependently of the first control resource set, and communicate with abase station based at least in part on control information identified asa result of the monitoring of the first search space or the monitoringof the second search space.

A non-transitory computer-readable medium for wireless communication ata user equipment (UE) is described. The non-transitory computer-readablemedium may include instructions operable to cause a processor toidentify a first control resource set and a second control resource set,wherein resources of the first control resource set at least partiallyoverlap with resources of the second control resource set, monitor afirst search space of the first control resource set, wherein themonitoring the first search space comprises rate-matching first downlinkcontrol channel resources of the first control resource set for thefirst search space independently of the second control resource set,monitor a second search space of the second control resource set,wherein the monitoring the second search space comprises rate-matchingsecond downlink control channel resources of the second control resourceset for the second search space independently of the first controlresource set, and communicate with a base station based at least in parton control information identified as a result of the monitoring of thefirst search space or the monitoring of the second search space.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for identifying first locations for afirst set of reference signals associated with the first controlresource set, wherein the monitoring the first search space comprisesrate matching the first downlink control channel resources around thefirst locations.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for identifying second locations for asecond set of reference signals associated with the second controlresource set, wherein the monitoring the second search space comprisesrate matching the second downlink control channel resources around thesecond locations.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the first locations coincidewith the second locations within the resources of the first controlresource set that overlap with the resources of the second controlresource set.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the first locations may benon-coincident with the second locations within the resources of thefirst control resource set that overlap with the resources of the secondcontrol resource set.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the monitoring the firstsearch space comprises rate matching the first downlink control channelresources to the second locations within the resources of the firstcontrol resource set that overlap with the resources of the secondcontrol resource set.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the rate matching the firstdownlink control channel resources to the second locations may be basedat least in part on a type of the first control resource set and a typeof the second control resource set.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the monitoring the firstsearch space comprises: demodulating one or more downlink controlchannel candidates of the first search space within the resources of thefirst control resource set that overlap with the resources of the secondcontrol resource set based at least in part on the first set ofreference signals.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for determining that at least onereference signal associated with the first control resource set may bein a portion of resources that overlap with the second control resourceset based at least in part on a type of the first control resource setand a type of the second control resource set.

A method of wireless communication at a user equipment (UE) isdescribed. The method may include identifying a first control resourceset configured for downlink control information for the UE, the firstcontrol resource set having first locations for a first set of referencesignals, identifying a second control resource set, wherein resources ofthe first control resource set at least partially overlap with resourcesof the second control resource set, and wherein second locations for asecond set of reference signals of the second control resource set arenon-coincident with the first locations within the resources of thefirst control resource set that overlap with the resources of the secondcontrol resource set, monitoring a first search space of the firstcontrol resource set, wherein the monitoring the first search spacecomprises rate matching first downlink control channel resources of thefirst control resource set around the first locations and the secondlocations within the resources of the first control resource set thatoverlap with the resources of the second control resource set, andcommunicating with a base station based at least in part on controlinformation identified as a result of the monitoring the first searchspace.

An apparatus for wireless communication is described. The apparatus mayinclude means for identifying a first control resource set configuredfor downlink control information for the UE, the first control resourceset having first locations for a first set of reference signals, meansfor identifying a second control resource set, wherein resources of thefirst control resource set at least partially overlap with resources ofthe second control resource set, and wherein second locations for asecond set of reference signals of the second control resource set arenon-coincident with the first locations within the resources of thefirst control resource set that overlap with the resources of the secondcontrol resource set, means for monitoring a first search space of thefirst control resource set, wherein the monitoring the first searchspace comprises rate matching first downlink control channel resourcesof the first control resource set around the first locations and thesecond locations within the resources of the first control resource setthat overlap with the resources of the second control resource set, andmeans for communicating with a base station based at least in part oncontrol information identified as a result of the monitoring the firstsearch space.

Another apparatus for wireless communication is described. The apparatusmay include a processor, memory in electronic communication with theprocessor, and instructions stored in the memory. The instructions maybe operable to cause the processor to identify a first control resourceset configured for downlink control information for the UE, the firstcontrol resource set having first locations for a first set of referencesignals, identify a second control resource set, wherein resources ofthe first control resource set at least partially overlap with resourcesof the second control resource set, and wherein second locations for asecond set of reference signals of the second control resource set arenon-coincident with the first locations within the resources of thefirst control resource set that overlap with the resources of the secondcontrol resource set, monitor a first search space of the first controlresource set, wherein the monitoring the first search space comprisesrate matching first downlink control channel resources of the firstcontrol resource set around the first locations and the second locationswithin the resources of the first control resource set that overlap withthe resources of the second control resource set, and communicate with abase station based at least in part on control information identified asa result of the monitoring the first search space.

A non-transitory computer-readable medium for wireless communication ata user equipment (UE) is described. The non-transitory computer-readablemedium may include instructions operable to cause a processor toidentify a first control resource set configured for downlink controlinformation for the UE, the first control resource set having firstlocations for a first set of reference signals, identify a secondcontrol resource set, wherein resources of the first control resourceset at least partially overlap with resources of the second controlresource set, and wherein second locations for a second set of referencesignals of the second control resource set are non-coincident with thefirst locations within the resources of the first control resource setthat overlap with the resources of the second control resource set,monitor a first search space of the first control resource set, whereinthe monitoring the first search space comprises rate matching firstdownlink control channel resources of the first control resource setaround the first locations and the second locations within the resourcesof the first control resource set that overlap with the resources of thesecond control resource set, and communicate with a base station basedat least in part on control information identified as a result of themonitoring the first search space.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for demodulating one or more downlinkcontrol channel candidates of the first search space within theresources of the first control resource set that overlap with theresources of the second control resource set based at least in part onthe first set of reference signals, wherein the communicating with thebase station may be based at least in part on the demodulating.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for determining that at least onereference signal associated with the first control resource set may bein a portion of resources that overlap with the second control resourceset based at least in part on a type of the first control resource setand a type of the second control resource set.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the monitoring the firstsearch space comprises spatially processing the resources of the firstcontrol resource set that overlap with the resources of the secondcontrol resource set based at least in part on the first set ofreference signals.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for identifying at least one physicalchannel transmitted on at least a portion of the first control resourceset, wherein a downlink control channel may be rate matched around theat least one physical channel.

In one example, a method of wireless communication at a UE is described.The method may include identifying an overlap in resources between afirst set of downlink control channel resources including a downlinkcontrol channel, and a second set of downlink control channel resources;identifying, based at least in part on the overlap, a set of referencesignals associated with the downlink control channel; and demodulatingthe downlink control channel based at least in part on the set ofreference signals.

In one example, an apparatus for wireless communication at a UE isdescribed. The apparatus may include means for identifying an overlap inresources between a first set of downlink control channel resourcesincluding a downlink control channel, and a second set of downlinkcontrol channel resources; means for identifying, based at least in parton the overlap, a set of reference signals associated with the downlinkcontrol channel; and means for demodulating the downlink control channelbased at least in part on the set of reference signals.

In one example, another apparatus for wireless communication at a UE isdescribed. The apparatus may include a processor, memory in electroniccommunication with the processor, and instructions stored in the memory.The instructions may be executable by the processor to identify anoverlap in resources between a first set of downlink control channelresources including a downlink control channel, and a second set ofdownlink control channel resources; to identify, based at least in parton the overlap, a set of reference signals associated with the downlinkcontrol channel; and to demodulate the downlink control channel based atleast in part on the set of reference signals.

In one example, a non-transitory computer-readable medium storingcomputer-executable code for wireless communication at a UE isdescribed. The code may be executable by a processor to identify anoverlap in resources between a first set of downlink control channelresources including a downlink control channel, and a second set ofdownlink control channel resources; to identify, based at least in parton the overlap, a set of reference signals associated with the downlinkcontrol channel; and to demodulate the downlink control channel based atleast in part on the set of reference signals.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the first set of downlinkcontrol channel resources may be a first search space within a firstdownlink control resource set and the second set of downlink controlchannel resources may be a second search space. In some examples, thesecond search space may be a subset of resources of the first downlinkcontrol resource set.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the first set of downlinkcontrol channel resources may be a first downlink control resource setand the second set of downlink control channel resources may be a seconddownlink control resource set.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for receiving at least a portion of thedownlink control channel on resources of the first set of downlinkcontrol channel resources within the overlap. In some examples, thedownlink control channel may be rate matched around the set of referencesignals. In some examples, the method, apparatus, and non-transitorycomputer-readable medium may further include processes, features, means,or instructions for determining whether the downlink control channel isfurther rate matched around at least one reference signal associatedwith a second downlink control channel associated with the second set ofdownlink control channel resources based at least in part on a type ofthe first set of downlink control channel resources and a type of thesecond set of downlink control channel resources. In some examples, themethod, apparatus, and non-transitory computer-readable medium mayfurther include processes, features, means, or instructions foridentifying at least one physical channel transmitted on at least aportion of the first set of downlink control channel resources, and thedownlink control channel may be further rate matched around the at leastone physical channel. In some examples, the method, apparatus, andnon-transitory computer-readable medium may further include processes,features, means, or instructions for determining whether at least onereference signal associated with a second downlink control channelassociated with the second set of downlink control channel resources ispresent in the overlap based at least in part on a type of the first setof downlink control channel resources and a type of the second set ofdownlink control channel resources. In some examples, the method,apparatus, and non-transitory computer-readable medium may furtherinclude processes, features, means, or instructions for spatiallyprocessing the set of reference signals associated with the downlinkcontrol channel based at least in part on the determining whether the atleast one reference signal associated with the second downlink controlchannel is present in the overlap. In some examples, the at least onereference signal associated with the second downlink control channel maycoincide with a reference signal of the set of reference signalsassociated with the downlink control channel.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for receiving the downlink controlchannel on resources of the first set of downlink control channelresources exclusive of the overlap. In some examples, the identifyingthe set of reference signals may include determining whether at leastone reference signal in the set of reference signals is located in theoverlap based at least in part on a type of the first set of downlinkcontrol channel resources.

In one example, a method of wireless communication at a base station isdescribed. The method may include identifying an overlap in resourcesbetween a first set of downlink control channel resources and a secondset of downlink control channel resources; identifying, based at leastin part on the overlap, a set of reference signals associated with adownlink control channel for transmission on the first set of downlinkcontrol channel resources; and transmitting the downlink control channeland the set of reference signals on the first set of downlink controlchannel resources.

In one example, an apparatus for wireless communication at a basestation is described. The apparatus may include means for identifying anoverlap in resources between a first set of downlink control channelresources and a second set of downlink control channel resources; meansfor identifying, based at least in part on the overlap, a set ofreference signals associated with a downlink control channel fortransmission on the first set of downlink control channel resources; andmeans for transmitting the downlink control channel and the set ofreference signals on the first set of downlink control channelresources.

In one example, another apparatus for wireless communication at a basestation is described. The apparatus may include a processor, memory inelectronic communication with the processor, and instructions stored inthe memory. The instructions may be executable by the processor toidentify an overlap in resources between a first set of downlink controlchannel resources and a second set of downlink control channelresources; to identify, based at least in part on the overlap, a set ofreference signals associated with a downlink control channel fortransmission on the first set of downlink control channel resources; andto transmit the downlink control channel and the set of referencesignals on the first set of downlink control channel resources.

In one example, a non-transitory computer-readable medium storingcomputer-executable code for wireless communication at a base station isdescribed. The code may be executable by a processor to identify anoverlap in resources between a first set of downlink control channelresources and a second set of downlink control channel resources; toidentify, based at least in part on the overlap, a set of referencesignals associated with a downlink control channel for transmission onthe first set of downlink control channel resources; and to transmit thedownlink control channel and the set of reference signals on the firstset of downlink control channel resources.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the first set of downlinkcontrol channel resources may be a first search space within a firstdownlink control resource set and the second set of downlink controlchannel resources may be a second search space. In some examples, thesecond search space may be a subset of resources of the first downlinkcontrol resource set.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the first set of downlinkcontrol channel resources may be a first downlink control resource setand the second set of downlink control channel resources may be a seconddownlink control resource set.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for transmitting at least a portion ofthe downlink control channel on resources of the first set of downlinkcontrol channel resources within the overlap. In some examples, themethod, apparatus, and non-transitory computer-readable medium mayfurther include processes, features, means, or instructions for ratematching the downlink control channel around the set of referencesignals. In some examples, the method, apparatus, and non-transitorycomputer-readable medium may further include processes, features, means,or instructions for determining whether to rate match the downlinkcontrol channel around at least one reference signal associated with asecond downlink control channel associated with the second set ofdownlink control channel resources based at least in part on a type ofthe first set of downlink control channel resources and a type of thesecond set of downlink control channel resources. In some examples, themethod, apparatus, and non-transitory computer-readable medium mayfurther include processes, features, means, or instructions for ratematching the downlink control channel around at least one physicalchannel transmitted on at least a portion of the first set of downlinkcontrol channel resources. In some examples, the method, apparatus, andnon-transitory computer-readable medium may further include processes,features, means, or instructions for determining whether to transmit atleast one reference signal associated with a second downlink controlchannel associated with the second set of downlink control channelresources in the overlap based at least in part on a type of the firstset of downlink control channel resources and a type of the second setof downlink control channel resources. In some examples, the method,apparatus, and non-transitory computer-readable medium may furtherinclude processes, features, means, or instructions for spatiallyprocessing the set of reference signals associated with the downlinkcontrol channel based at least in part on the determining whether the atleast one reference signal associated with the second downlink controlchannel is to be transmitted in the overlap. In some examples, the atleast one reference signal associated with the second downlink controlchannel may coincide with a reference signal of the set of referencesignals associated with the downlink control channel.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for transmitting the downlink controlchannel on resources of the first set of downlink control channelresources exclusive of the overlap. In some examples, the identifyingthe set of reference signals may include determining whether to transmitat least one reference signal in the set of reference signals in theoverlap based at least in part on a type of the first set of downlinkcontrol channel resources.

The foregoing has outlined rather broadly the features and technicaladvantages of examples according to the disclosure in order that thedetailed description that follows may be better understood. Additionalfeatures and advantages will be described hereinafter. The conceptionand specific examples disclosed may be readily utilized as a basis formodifying or designing other structures for carrying out the samepurposes of the present disclosure. Such equivalent constructions do notdepart from the scope of the appended claims. Characteristics of theconcepts disclosed herein, both their organization and method ofoperation, together with associated advantages will be better understoodfrom the following description when considered in connection with theaccompanying figures. Each of the figures is provided for the purpose ofillustration and description only, and not as a definition of the limitsof the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

A further understanding of the nature and advantages of the presentinvention may be realized by reference to the following drawings. In theappended figures, similar components or features may have the samereference label. Further, various components of the same type may bedistinguished by following the reference label by a dash and a secondlabel that distinguishes among the similar components. If only the firstreference label is used in the specification, the description isapplicable to any one of the similar components having the same firstreference label irrespective of the second reference label.

FIG. 1 shows an example of a wireless communication system, inaccordance with various aspects of the present disclosure;

FIG. 2 shows a frequency range in which overlapping downlink controlresource sets are defined, in accordance with various aspects of thepresent disclosure;

FIG. 3 shows a downlink control resource set 300 in which overlappingsearch spaces 305 and 310 are defined, in accordance with variousaspects of the present disclosure;

FIGS. 4 and 5 show a frequency range in which overlapping sets ofdownlink control channel resources are defined, in accordance withvarious aspects of the present disclosure;

FIG. 6 shows a block diagram of an apparatus for use in wirelesscommunication, in accordance with various aspects of the presentdisclosure;

FIG. 7 shows a block diagram of a wireless communication manager, inaccordance with various aspects of the present disclosure;

FIG. 8 shows a block diagram of an apparatus for use in wirelesscommunication, in accordance with various aspects of the presentdisclosure;

FIG. 9 shows a block diagram of a wireless communication manager, inaccordance with various aspects of the present disclosure;

FIG. 10 shows a block diagram of a UE for use in wireless communication,in accordance with various aspects of the present disclosure;

FIG. 11 shows a block diagram of a base station for use in wirelesscommunication, in accordance with various aspects of the presentdisclosure;

FIGS. 12-14 are flow charts illustrating examples of methods forwireless communication at a UE, in accordance with various aspects ofthe present disclosure; and

FIGS. 15-20 are flow charts illustrating examples of methods forwireless communication at a base station, in accordance with variousaspects of the present disclosure.

DETAILED DESCRIPTION

In some wireless communication systems (e.g., in an NR or 5G wirelesscommunication system), a control resource set (e.g., a downlink controlresource set) and/or search space may configured for transmission of adownlink control channel. For purposes of this disclosure, a downlinkcontrol resource set includes a set of resources on which one or moresearch spaces can be defined, or a set of resources on which one or moredownlink control channels may be transmitted. One or more downlinkcontrol channels may be transmitted over a downlink control resourceset, which may include one or more search spaces defining regions fortransmission of different downlink control channels. A downlink controlchannel may be transmitted on one of multiple candidate locations withina search space. Reference signals (e.g., demodulation reference signals(DMRS)) may be associated with downlink control resource sets, searchspaces, or downlink control channels.

A downlink control resource set may be common or UE-specific. A searchspace may also be common or UE-specific. A UE-specific downlink controlresource set or UE-specific search space may be configured for a UE orgroup of UEs. In some cases, multiple downlink control resource sets maybe configured. For example, a base station may transmit configurationinformation for a common downlink control resource set in a masterinformation block (MIB) or other system information (SI) transmission,and may transmit configuration information for one or more UE-specificdownlink control resource sets in radio resource control (RRC)signaling. The base station may also transmit, in SI or RRC signalingfor example, configuration information for one or more search spacesdefined within each downlink control resource set.

In some cases, different downlink control resource sets, or differentsearch spaces (e.g., within the same or different downlink controlresource sets), may overlap. In these cases, a base station or UE maydetermine what signals may be transmitted/received in an overlap inresources between downlink control resource sets and/or search spaces. Abase station or UE may also determine whether to rate match a downlinkcontrol channel (or whether a downlink control channel is rate matched)around reference signals associated with other downlink control resourcesets, other search spaces, or other physical channels within theoverlap.

The following description provides examples, and is not limiting of thescope, applicability, or examples set forth in the claims. Changes maybe made in the function and arrangement of elements discussed withoutdeparting from the scope of the disclosure. Various examples may omit,substitute, or add various procedures or components as appropriate. Forinstance, the methods described may be performed in an order differentfrom that described, and various operations may be added, omitted, orcombined. Also, features described with respect to some examples may becombined in some other examples.

FIG. 1 shows an example of a wireless communication system 100, inaccordance with various aspects of the present disclosure. The wirelesscommunication system 100 includes base stations 105, UEs 115, and a corenetwork 130. In some examples, the wireless communication system 100 maybe a Long Term Evolution (LTE), LTE-Advanced (LTE-A) network, or a NewRadio (NR) network. In some cases, wireless communication system 100 maysupport enhanced broadband communications, ultra-reliable (i.e., missioncritical) communications, low latency communications, and communicationswith low-cost and low-complexity devices.

Base stations 105 may wirelessly communicate with UEs 115 via one ormore base station antennas. Each base station 105 may providecommunication coverage for a respective geographic coverage area 110.Communication links 125 shown in wireless communication system 100 mayinclude uplink (UL) transmissions from a UE 115 to a base station 105,or downlink (DL) transmissions, from a base station 105 to a UE 115.Control information and data may be multiplexed on an uplink channel ordownlink according to various techniques. Control information and datamay be multiplexed on a downlink channel, for example, using timedivision multiplexing (TDM) techniques, frequency division multiplexing(FDM) techniques, or hybrid TDM-FDM techniques.

UEs 115 may be dispersed throughout the wireless communication system100, and each UE 115 may be stationary or mobile. A UE 115 may also bereferred to as a mobile station, a subscriber station, a mobile unit, asubscriber unit, a wireless unit, a remote unit, a mobile device, awireless device, a wireless communications device, a remote device, amobile subscriber station, an access terminal, a mobile terminal, awireless terminal, a remote terminal, a handset, a user agent, a mobileclient, a client, or some other suitable terminology. A UE 115 may alsobe a cellular phone, a personal digital assistant (PDA), a wirelessmodem, a wireless communication device, a handheld device, a tabletcomputer, a laptop computer, a cordless phone, a personal electronicdevice, a handheld device, a personal computer, a wireless local loop(WLL) station, an Internet of things (IoT) device, an Internet ofEverything (IoE) device, a machine type communication (MTC) device, anappliance, an automobile, or the like.

In some cases, a UE 115 may also be able to communicate directly withother UEs (e.g., using a peer-to-peer (P2P) or device-to-device (D2D)protocol). One or more of a group of UEs 115 utilizing D2Dcommunications may be within the geographic coverage area 110 of a cell.Other UEs 115 in such a group may be outside the geographic coveragearea 110 of a cell, or otherwise unable to receive transmissions from abase station 105. In some cases, groups of UEs 115 communicating via D2Dcommunications may utilize a one-to-many (1:M) system in which each UE115 transmits to every other UE 115 in the group. In some cases, a basestation 105 facilitates the scheduling of resources for D2Dcommunications. In other cases, D2D communications are carried outindependent of a base station 105.

Some UEs 115, such as MTC or IoT devices, may be low cost or lowcomplexity devices, and may provide for automated communication betweenmachines, i.e., Machine-to-Machine (M2M) communication. M2M or MTC mayrefer to data communication technologies that allow devices tocommunicate with one another or a base station without humanintervention. For example, M2M or MTC may refer to communications fromdevices that integrate sensors or meters to measure or captureinformation and relay that information to a central server orapplication program that can make use of the information or present theinformation to humans interacting with the program or application. SomeUEs 115 may be designed to collect information or enable automatedbehavior of machines. Examples of applications for MTC devices includesmart metering, inventory monitoring, water level monitoring, equipmentmonitoring, healthcare monitoring, wildlife monitoring, weather andgeological event monitoring, fleet management and tracking, remotesecurity sensing, physical access control, and transaction-basedbusiness charging.

In some cases, an MTC device may operate using half-duplex (one-way)communications at a reduced peak rate. MTC devices may also beconfigured to enter a power saving “deep sleep” mode when not engagingin active communications. In some cases, MTC or IoT devices may bedesigned to support mission critical functions and wirelesscommunication system may be configured to provide ultra-reliablecommunications for these functions.

Base stations 105 may communicate with the core network 130 and with oneanother. For example, base stations 105 may interface with the corenetwork 130 through backhaul links 132 (e.g., S1, etc.). Base stations105 may communicate with one another over backhaul links 134 (e.g., X2,etc.) either directly or indirectly (e.g., through core network 130).Base stations 105 may perform radio configuration and scheduling forcommunication with UEs 115, or may operate under the control of a basestation controller (not shown). In some examples, base stations 105 maybe macro cells, small cells, hot spots, or the like. Base stations 105may also be referred to as eNodeBs (eNBs) or gNodeBs (gNBs).

A base station 105 may be connected by an S1 interface to the corenetwork 130. The core network may be an evolved packet core (EPC), whichmay include at least one mobility management entity (MME), at least oneserving gateway (S-GW), and at least one Packet Data Network (PDN)gateway (P-GW). The MME may be the control node that processes thesignaling between the UE 115 and the EPC. All user Internet Protocol(IP) packets may be transferred through the S-GW, which itself may beconnected to the P-GW. The P-GW may provide IP address allocation aswell as other functions. The P-GW may be connected to the networkoperators IP services. The operators IP services may include theInternet, the Intranet, an IP Multimedia Subsystem (IMS), and aPacket-Switched (PS).

The core network 130 may provide user authentication, accessauthorization, tracking, IP connectivity, and other access, routing, ormobility functions. At least some of the network devices, such as basestation 105 may include subcomponents such as an access network entity,which may be an example of an access node controller (ANC). Each accessnetwork entity may communicate with a number of UEs 115 through a numberof other access network transmission entities, each of which may be anexample of a smart radio head, or a transmission/reception point (TRP).In some configurations, various functions of each access network entityor base station 105 may be distributed across various network devices(e.g., radio heads and access network controllers) or consolidated intoa single network device (e.g., a base station 105).

At times, a base station 105 may transmit a downlink control channel toone or more UEs 115. A base station 105 may also transmit differentdownlink control channels to different UEs 115. Some downlink controlchannels may be transmitted as common downlink control channels (e.g.,to all UEs 115 within a base station's coverage area 110). Otherdownlink control channels may be transmitted as UE-specific downlinkcontrol channels (e.g., to one or a subset of UEs 115 within a basestation's coverage area 110).

FIG. 2 shows a frequency range 200 in which overlapping downlink controlresource sets 205 are defined, in accordance with various aspects of thepresent disclosure. Although the overlapping downlink control resourcesets 205-a and 205-b are shown side-by-side, this is just forillustration purposes, and the downlink control resource sets 205-a and205-b include the same resources within an overlap 215 (i.e., theoverlap 215 of the downlink control resource sets 205-a and 205-bincludes the same frequency resources in the same time period). In someexamples, the downlink control resource sets 205 and 205-b may span morethan one time period (e.g., more than one symbol period), and mayoverlap in frequency in some or all of the time periods.

In some examples, each of the downlink control resource sets 205-a and205-b may be common or UE-specific (e.g., a first downlink controlresource set 205-a may be common and a second downlink control resourceset 205-b may be UE-specific, or both downlink control resource sets205-a and 205-b may be UE-specific, etc.). The first downlink controlresource set 205-a may be used to transmit/receive a first downlinkcontrol channel, and the second downlink control resource set 205-b maybe used to transmit/receive a second downlink control channel. Thedownlink control channels may or may not be transmitted at the same time(e.g., within the same slot), and each may use a portion of therespective downlink control resource set, such that only one (orneither) of the downlink control channels may be transmitted in theoverlap 215 for a given slot and spatial layer.

FIG. 3 shows a downlink control resource set 300 in which overlappingsearch spaces 305 are defined, in accordance with various aspects of thepresent disclosure. Although the overlapping search spaces 310-a and310-b are shown side-by-side, this is just for illustration purposes,and the search spaces 310-a and 310-b are defined to include the sameresources within an overlap 315 (i.e., the overlap 315 of the searchspaces 310-a and 310-b includes the same frequency resources in the sametime period). In some examples, the search spaces 310-a and 310-b mayspan more than one time period (e.g., more than one symbol period of aslot), and may overlap in frequency in some or all of the time periods.

In some examples, each of the search spaces 310-a and 310-b may becommon or UE-specific (e.g., a first search space 310-a may be commonand a second search space 310-b may be UE-specific, or both searchspaces 310-a and 310-b may be UE-specific, etc.). The first search space310-a may be used to transmit/receive a first downlink control channel,and the second search space 310-b may be used to transmit/receive asecond downlink control channel. The downlink control channels may ormay not be transmitted at the same time (e.g., within the same slot),and each may use a portion of the respective search spaces, such thatonly one (or neither) of the downlink control channels may betransmitted in the overlap 315 for a given slot and spatial layer. Insome examples, the search spaces 310-a and 310-b may be configuredwithin a same downlink control resource set 205-c. In other examples,the search spaces 310-a and 310-b may be configured within differentdownlink control resource sets 205 (not shown).

Given the overlap 215 or the overlap 315 described with reference toFIG. 2 or 3, one or more rules may be established fortransmitting/receiving a downlink control channel in downlink controlresource sets or search spaces having the overlap 215 or overlap 315. Insome examples, a first rule may indicate that signaling associated withthe first downlink control resource set 205-a (e.g., a downlink controlchannel or reference signals) and signaling associated with the seconddownlink control resource set 205-b may not be transmitted onoverlapping resources within the overlap 215. The rule may also beapplied to signaling associated with the first search space 310-a (e.g.,a downlink control channel or reference signals) and signalingassociated with the second search space 310-b (e.g., a downlink controlchannel or reference signals). In some examples, the first rule may beapplied based on a “type” associated with the downlink control resourcesets 205 or based on a type associated with the search spaces 310-a. Forexample, the first rule may be applied when both of the downlink controlresource sets 205-a and 205-b (or both of the search spaces 310-a and310-b) are UE-specific, but not when the downlink control resource sets205-a and 205-b (or search spaces 310-a and 310-b) are of differenttypes (e.g., when one of the downlink control resource sets 205 and205-b is UE-specific, and the other is common).

In some examples, a second rule may indicate that some signalingassociated with overlapping downlink control resource sets 205 (e.g.,multiple downlink control channels) may not be transmitted onoverlapping resources, while other signaling (e.g., reference signalsassociated with one downlink control resource set and a downlink controlchannel for another downlink control resource set) may be transmitted onoverlapping resources within the overlap 215. The rule may also beapplied to signaling associated with the search spaces 310 (e.g.,multiple downlink control channels may not overlap while referencesignals associated with one search space may overlap with a downlinkcontrol channel transmitted in another search space). In some examples,the second rule may be applied based on a type associated with thedownlink control resource sets 205, or based on a type associated withthe search spaces 310. For example, the second rule may be applied whenthe downlink control resource sets 205 (or search spaces 310) are ofdifferent types (e.g., when one of the downlink control resource sets205 is UE-specific, and the other is common), but not when both of thedownlink control resource sets 205 (or both of the search spaces 310)are of the same type (e.g., UE-specific). In some examples, referencesignals associated with a common downlink control resource set or commonsearch space may be transmitted across the common downlink controlresource set or common search space in each slot.

In some examples, a third rule may indicate that signaling associatedwith the first downlink control resource set 205-a (e.g., a downlinkcontrol channel or reference signals) and signaling associated with thesecond downlink control resource set 205-b may be transmitted onoverlapping resources within the overlap 215. For example, the thirdrule may be applied when spatial processing is used to distinguish thesignaling for overlapping resources. In some examples, the spatialprocessing may include beamforming (i.e., transmitting on directionalbeams) or space division multiplexing. For example, the third rule maybe applied when it is determined that downlink control resource sets205, or search spaces 310 are configured on spatially orthogonalresources or beamforming is applied to at least one of the downlinkcontrol resource sets 205 or search spaces 310. In some examples,UE-specific downlink control resource sets 205 or search spaces 310 mayhave beamforming applied, and therefore a downlink control channeltransmission or reference signals may be transmitted on resources of aUE-specific downlink control resource set 205 or search space 310 thatoverlaps with a downlink control channel transmission or referencesignals transmitted on a non-beamformed (e.g., common) downlink controlresource set 205 or search space 310.

When reference signals or physical channels (e.g., a downlink controlchannel or other physical channel) are simultaneously transmitted onoverlapping resources of different downlink control resource sets (or indifferent search spaces), rate matching may need to take into accountthe concurrent transmissions.

FIG. 4 shows a frequency range 400 in which overlapping sets of downlinkcontrol channel resources 405 and 410 are defined, in accordance withvarious aspects of the present disclosure. The overlapping sets ofdownlink control channel resources may be overlapping downlink controlresource sets, as described with reference to FIG. 2, or overlappingsearch spaces, as described with reference to FIG. 3. The overlappingsets of downlink control channel resources 405 and 410 may overlap in aregion 425. A first set of downlink control channel resources may beused to transmit a first downlink control channel associated with afirst set of reference signals 415, and a second set of downlink controlchannel resources may be used to transmit a second downlink controlchannel associated with a second set of reference signals 420. The firstset of reference signals 415 and second set of reference signals 420 maybe transmitted on different resource elements (REs) within the region425.

In some examples, the first downlink control channel may assume theexistence of just its own set of reference signals (i.e., the first setof reference signals 415) and may be rate matched to just the first setof reference signals 415. Similarly, the second downlink control channelmay assume the existence of just its own set of reference signals (i.e.,the second set of reference signals 420) and may be rate matched to justthe second set of reference signals 420.

In some examples, the first downlink control channel may assume theexistence of the first set of reference signals 415 and the second setof reference signals 420, and may be rate matched to both the first setof reference signals 415 and the second set of reference signals 420.Similarly, the second downlink control channel may assume the existenceof both the first set of reference signals 415 and the second set ofreference signals 420, and may be rate matched to both the first set ofreference signals 415 and the second set of reference signals 420. Adetermination of rate matching may depend on the types of downlinkcontrol channel resources. For example, where a downlink control channelin UE-specific downlink control channel resources overlaps with a set ofcommon downlink control channel resources, a determination may be madethat the downlink control channel is rate matched around the first andsecond sets of reference signals. In contrast, where a downlink controlchannel in a first set of UE-specific downlink control channel resourcesoverlaps with a second set of UE-specific downlink control channelresources, a determination may be made that the downlink control channelis rate matched around only the first set of reference signals.

FIG. 5 shows a frequency range 500 in which overlapping sets of downlinkcontrol channel resources 505 and 510 are defined, in accordance withvarious aspects of the present disclosure. The overlapping sets ofdownlink control channel resources may be overlapping downlink controlresource sets, as described with reference to FIG. 2, or overlappingsearch spaces, as described with reference to FIG. 3. The overlappingsets of downlink control channel resources 505 and 510 may overlap in aregion 525. A first set of downlink control channel resources may beused to transmit a first downlink control channel associated with afirst set of reference signals 515, and a second set of downlink controlchannel resources may be used to transmit a second downlink controlchannel associated with a second set of reference signals 520. The firstset of reference signals 515 and second set of reference signals 520 maybe configured for transmission on the same REs within the region 525(i.e., the REs used by the first set of reference signals 515 and thesecond set of reference signals 520, within the region 525, maycoincide).

Where a downlink control channel of a first set of downlink channelresources is transmitted on resources that overlap a second set ofdownlink channel resources having reference signals configured fortransmission on the same REs, rate matching within the overlappingresources may be to just its own set of reference signals (i.e., thefirst set of reference signals 515). Where REs are shared for differentsets of downlink channel resources, UEs may not assume the presence ofreference signals in regions of overlap with other sets of downlinkchannel resources. For example, where a common set of downlink controlchannel resources 505 overlaps with a UE-specific set of downlinkcontrol channel resources 510, a UE may not utilize portions of areference signal for the UE-specific set of downlink control channelresources 510 in the region 525 unless part of a downlink controlchannel. That is, the second set of reference signals 520 of region 525that are part of a downlink control channel (e.g., within CCEsassociated with the downlink control channel) may be utilized by the UE,while any others of the second set of reference signals 520 of region525 may be not utilized by the UE for channel estimation or demodulationof the downlink control channel.

In some examples, a downlink control channel of a set of downlinkcontrol channel resources may be rate matched to other physical channelsof its own set of downlink control channel resources or other sets ofdownlink control channel resources. In some cases, determination of theother physical channels may be based at least in part on the type ofdownlink control channel resources on which the downlink control channelis transmitted (e.g., common or UE-specific), or based at least in parton the type of the other sets of downlink control channel resources. Forexample, a UE may detect a downlink control channel of a set ofUE-specific downlink control channel resources that overlaps with a setof common downlink control channel resources, and determine the presenceof a physical channel in the set of common downlink control channelresources used for rate matching based on the type of the set of commondownlink control channel resources.

As described above with reference to FIGS. 4 and 5, a UE 115 may beconfigured to receive and decode control information via multiplecontrol resource sets having overlapped resources. The control resourcesets in a given transmission time interval (e.g., subframe, slot,mini-slot, etc.) may be overlapped in a variety of different ways. Forexample, different control resource sets may partially or fully overlap,and partially overlapping control resource sets may include coincidentor non-coincident reference signals. For example, a first controlresource set may have a starting resource block or subcarrier that isdifferent than a second control resource set, resulting in the referencesignals of the first control resource set being offset from thereference signals of the second control resource set, as is shown inFIG. 4. Alternatively, the reference signals of the first controlresource set may be aligned with the reference signals of the secondcontrol resource set, as is shown in FIG. 5.

The UE 115 may monitor a first search space of the first controlresource set. As part of the monitoring, the UE 115 may rate-match firstdownlink control channel resources of the first control resource set forthe first search space independently of the second control resource set.Referring back to FIG. 4, UE 115 may monitor first downlink controlchannel resources 425 of the first control resource set 405independently of the second control resource set 410 as shown in controlresource mapping 450. For example, UE 115 may rate match the firstdownlink control channel resources 425 based on the first set ofreference signals 415 and independently of the second set of referencesignals 420. That is, UE 115 may rate match the first downlink controlchannel resources 425 to resources of the first control resource set 405to which the second set of reference signals 420 are mapped. The UE 115may be configured with one or more search spaces for the first controlresource set 405, and may monitor the one or more search spaces mappedto the first downlink control channel resources 425. Similarly, as shownin control resource mapping 550 in FIG. 5, the UE may rate-match firstdownlink control channel resources 525 of the first control resource set505 for the first search space independently of the second controlresource set 510 where reference signals for the first and secondcontrol resource sets are coincident in the overlapping resources of thecontrol resource sets.

As also shown in control resource mappings 450 and 550 in FIGS. 4 and 5,the UE 115 may also monitor a second search space of the second controlresource set. As part of the monitoring, the UE 115 may rate-matchsecond downlink control channel resources 430, 530 of the second controlresource set 410, 510 for the second search space independently of thefirst control resource set 405, 505.

As part of the monitoring of both a first search space in a firstcontrol resource set and a second search space in a second controlresource set, the UE 115 may identify locations for the sets ofreference signals associated with their respective control resourcesets. For example, monitoring the first search space by the UE 115 mayinclude rate matching the first downlink control channel resourcesaround locations of a first set of references signals associated withthe first control resource set. Further, monitoring the second searchspace by the UE 115 may include rate matching the second downlinkcontrol channel resources around locations of a second set of referencessignals associated with the second control resource set. In some cases,as is shown in FIG. 4, the locations of the reference signals in thedifferent control resource sets may be non-coincident. In some cases, asis shown in FIG. 5, the locations of the reference signals in thedifferent control resource sets may coincide. Thus, when demodulatingone or more downlink control channel candidates of the first searchspace within the resources of the first control resource set thatoverlap with the resources of the second control resource set, the UE115 may assume the presence of the first set of reference signals forchannel estimation for the demodulating. In addition, when demodulatingone or more downlink control channel candidates of the second searchspace within the resources of the second control resource set thatoverlap with the resources of the first control resource set, the UE 115may assume the presence of the second set of reference signals forchannel estimation for the demodulating. In these examples, coincidentresources of the first and second downlink control channel resources maynot be used at the same time (e.g., in overlapping time resources).

In some cases, the UE 115 may rate match downlink control channelresources associated with a first search space and a first controlresource set around locations of reference signals for a second searchspace and a second control resource set. For example, where coincidentuse of control channel resources is applicable (e.g., MIMO), the controlinformation may be multiplexed over multiple layers in the sametime-frequency resources but reference signals may be transmitted usingorthogonal time-frequency resources. Thus, when two control resourcesets overlap, control information for one control resource set may notbe present in the resource elements that contain reference signals forthe other control resource set. For example, as shown in controlresource mapping 455 in FIG. 4, first downlink control channel resources425 may be rate matched around the first set of reference signals 415and the second set of reference signals 420 in the portion of the firstcontrol resource set 405 that overlaps the second control resource set410. Similarly, the second downlink control channel resources 430 may berate matched around the first set of reference signals 415 and thesecond set of reference signals 420 in the portion of the second controlresource set 410 that overlaps the first control resource set 405.

In some cases, the UE 115 may determine a type of control resource setsthat may be overlapped. The UE 115 may apply rate matching based on thetypes of control resource sets that may be overlapped. Types of controlresource sets may include a common control resource set or a UE-specificcontrol resource set.

Once the UE 115 identifies the reference signals for either controlresource set or both control resource sets, the UE 115 may demodulateone or more blind decoding candidates (e.g., downlink control channelcandidates) of the search space using the identified reference signals.In some cases, the UE 115 may apply rate matching to portions of thecontrol resource sets that may overlap (when such information is known).In some cases, the UE 115 may apply different rules to portions of thesearch spaces that overlap and portions of the search spaces that do notoverlap.

In some cases, overlapping control resource sets and/or overlappingsearch spaces may be used in the context of a multiple in multiple out(MIMO) communications. For example, such overlaps may be in multi-userMIMO (MU-MIMO) communications. The UE 115 may spatially process theresources of one of the control resource sets that overlaps anothercontrol resource set based on the reference signals of the first controlresource set. It should be noted that control resource mappings 450,455, and 550 should be understood as overlapping in time and areillustrated side-by-side for ease of illustration.

FIG. 6 shows a block diagram 600 of an apparatus 605 for use in wirelesscommunication, in accordance with various aspects of the presentdisclosure. The apparatus 605 may be an example of aspects of one ormore of the UEs described with reference to FIG. 1. The apparatus 605may include a receiver 610, a wireless communication manager 615, and atransmitter 620. The apparatus 605 may also include a processor. Each ofthese components may be in communication with one another (e.g., via oneor more buses).

The receiver 610 may receive data or control signals or information(i.e., transmissions), some or all of which may be associated withvarious information channels (e.g., data channels, control channels,etc.). In some examples, the receiver 610 may be used to receive adownlink control channel and associated set of reference signals.Received signals or information, or measurements performed thereon, maybe passed to other components of the apparatus 605.

The transmitter 620 may transmit data or control signals or information(i.e., transmissions) generated by other components of the apparatus605, some or all of which may be associated with various informationchannels (e.g., data channels, control channels, etc.). In someexamples, the transmitter 620 may be collocated with the receiver 610 ina transceiver. For example, the transmitter 620 and receiver 610 may bean example of aspects of the transceiver(s) 1030 described withreference to FIG. 10.

The wireless communication manager 615 and/or at least some of itsvarious sub-components may be implemented in hardware, software executedby a processor, firmware, or any combination thereof. If implemented insoftware executed by a processor, the functions of the wirelesscommunication manager 615 and/or at least some of its varioussub-components may be executed by a general-purpose processor, a digitalsignal processor (DSP), an application-specific integrated circuit(ASIC), a field-programmable gate array (FPGA) or other programmablelogic device, discrete gate or transistor logic, discrete hardwarecomponents, or any combination thereof designed to perform the functionsdescribed in the present disclosure.

The wireless communication manager 615 and/or at least some of itsvarious sub-components may be physically located at various positions,including being distributed such that portions of functions areimplemented at different physical locations by one or more physicaldevices. In some examples, the wireless communication manager 615 and/orat least some of its various sub-components may be a separate anddistinct component in accordance with various aspects of the presentdisclosure. In other examples, the wireless communication manager 615and/or at least some of its various sub-components may be combined withone or more other hardware components, including but not limited to anI/O component, a transceiver, another computing device, one or moreother components described in the present disclosure, or a combinationthereof, in accordance with various aspects of the present disclosure.The wireless communication manager 615 may include a resource setoverlap identifier 625, a reference signal identifier 630, a demodulator635, and a search space monitor 640.

The resource set overlap identifier 625 may be used to identify anoverlap in resources between a first set of downlink control channelresources including a downlink control channel, and a second set ofdownlink control channel resources, as described for example withreference to FIGS. 2-5. In some examples, the first set of downlinkcontrol channel resources may be a first search space within a downlinkcontrol resource set, and the second set of downlink control channelresources may be a second search space. In other examples, the first setof downlink control channel resources may be a first downlink controlresource set and the second set of downlink control channel resourcesmay be a second downlink control resource set (and in some of theseexamples, the first downlink control channel may be further included ina search space of the first downlink control resource set).

The reference signal identifier 630 may be used to identify, based atleast in part on the overlap, a set of reference signals associated withthe downlink control channel, as described for example with reference toFIGS. 2-5.

Search space monitor 640 may identify a first control resource set and asecond control resource set, where resources of the first controlresource set at least partially overlap with resources of the secondcontrol resource set, identify at least one physical channel transmittedon at least a portion of the first control resource set, where adownlink control channel is rate matched around the at least onephysical channel, monitor a second search space of the second controlresource set, where the monitoring the second search space includesrate-matching second downlink control channel resources of the secondcontrol resource set for the second search space independently of thefirst control resource set, communicate with a base station based oncontrol information identified as a result of the monitoring of thefirst search space or the monitoring of the second search space, monitora first search space of the first control resource set, where themonitoring the first search space includes rate-matching first downlinkcontrol channel resources of the first control resource set for thefirst search space independently of the second control resource set,identify a second control resource set, where resources of the firstcontrol resource set at least partially overlap with resources of thesecond control resource set, and where second locations for a second setof reference signals of the second control resource set arenon-coincident with the first locations within the resources of thefirst control resource set that overlap with the resources of the secondcontrol resource set, monitor a first search space of the first controlresource set, where the monitoring the first search space includes ratematching first downlink control channel resources of the first controlresource set around the first locations and the second locations withinthe resources of the first control resource set that overlap with theresources of the second control resource set, communicate with a basestation based on control information identified as a result of themonitoring the first search space, and

Search space monitor 640 may identify a first control resource setconfigured for downlink control information for the UE, the firstcontrol resource set having first locations for a first set of referencesignals. In some cases, the monitoring the first search space includesrate matching the first downlink control channel resources to the secondlocations within the resources of the first control resource set thatoverlap with the resources of the second control resource set. In somecases, the rate matching the first downlink control channel resources tothe second locations is based on a type of the first control resourceset and a type of the second control resource set. In some cases, themonitoring the first search space includes spatially processing theresources of the first control resource set that overlap with theresources of the second control resource set based on the first set ofreference signals.

In some examples, the receiver 610 may be used to receive the downlinkcontrol channel on a subset of resources of the first search space(e.g., when the identified overlap is between the first search space andthe second search space), as described for example with reference toFIGS. 2-5. The subset of resources may be at least partially within theoverlap.

The demodulator 635 may be used to demodulate the downlink controlchannel based at least in part on the set of reference signals, asdescribed for example with reference to FIGS. 2-5.

FIG. 7 shows a block diagram 700 of a wireless communication manager715, in accordance with various aspects of the present disclosure. Thewireless communication manager 715 may be an example of aspects of thewireless communication manager described with reference to FIG. 6. Thewireless communication manager 715 may include a resource set overlapidentifier 725, a reference signal identifier 730, an optional ratematch determiner 735, an optional spatial processor 740, and ademodulator 745. Each of these components may communicate, directly orindirectly, with one another (e.g., via one or more buses). The resourceset overlap identifier 725, reference signal identifier 730, anddemodulator 745 may be examples of the overlap identifier 625, referencesignal identifier 630, demodulator 635, and a search space monitor 640described with reference to FIG. 6.

The resource set overlap identifier 725 may be used to identify anoverlap in resources between a first set of downlink control channelresources including a downlink control channel, and a second set ofdownlink control channel resources, as described for example withreference to FIGS. 2-5. In some examples, the first set of downlinkcontrol channel resources may be a first search space within a firstdownlink control resource set, and the second set of downlink controlchannel resources may be a second search space, which may be within thefirst downlink control resource set or a second downlink controlresource set. In other examples, the first set of downlink controlchannel resources may be a first downlink control resource set and thesecond set of downlink control channel resources may be a seconddownlink control resource set (and in some of these examples, the firstdownlink control channel may be further included in a search space ofthe first downlink control resource set).

The reference signal identifier 730 may be used to identify, based atleast in part on the overlap, a set of reference signals associated withthe downlink control channel, as described for example with reference toFIGS. 2-5. In some examples, identifying the set of reference signalsmay include determining whether at least one reference signal in the setof reference signals is located in the overlap based at least in part ona type of the first set of downlink control channel resources.

The rate match determiner 735 may be used to determine whether thedownlink control channel is rate matched around at least one referencesignal associated with a second downlink control channel associated withthe second set of downlink control channel resources, as described forexample with reference to FIGS. 2-5. The determination may be based atleast in part on a type of the first set of downlink control channelresources and a type of the second set of downlink control channelresources.

The rate match determiner 735 may also or alternatively be used toidentify at least one physical channel transmitted on at least a portionof the first set of downlink control channel resources, as described forexample with reference to FIGS. 2-5.

The reference signal identifier 730 may also be used to determinewhether at least one reference signal associated with the second set ofdownlink control channel resources is present in the overlap, asdescribed for example with reference to FIGS. 2-5. The determination maybe based at least in part on the type of the first set of downlinkcontrol channel resources and the type of the second set of downlinkcontrol channel resources. In some examples, the at least one referencesignal associated with the second downlink control channel may coincidewith a reference signal of the set of reference signals associated withthe downlink control channel.

Reference signal identifier 730 may identify first locations for a firstset of reference signals associated with the first control resource set,where the monitoring the first search space includes rate matching thefirst downlink control channel resources around the first locations,identify second locations for a second set of reference signalsassociated with the second control resource set, where the monitoringthe second search space includes rate matching the second downlinkcontrol channel resources around the second locations, and determinethat at least one reference signal associated with the first controlresource set is in a portion of resources that overlap with the secondcontrol resource set based on a type of the first control resource setand a type of the second control resource set. In some cases, the firstlocations coincide with the second locations within the resources of thefirst control resource set that overlap with the resources of the secondcontrol resource set. In some cases, the first locations arenon-coincident with the second locations within the resources of thefirst control resource set that overlap with the resources of the secondcontrol resource set.

In some examples, a receiver of an apparatus including the wirelesscommunication manager 715 may be used to receive at least a portion ofthe downlink control channel on resources of the first set of downlinkcontrol channel resources within the overlap, as described for examplewith reference to FIGS. 2-5. In some of these examples, the downlinkcontrol channel may be rate matched around the set of reference signals.The downlink control channel may also or alternatively be rate matchedaround the at least one reference signal associated with the seconddownlink control channel or the at least one physical channel. In otherexamples, the receiver of the apparatus including the wirelesscommunication manager 715 may be used to receive the downlink controlchannel on resources of the first set of downlink control channelresources exclusive of the overlap, as described for example withreference to FIGS. 2-5.

The spatial processor 740 may be used to process the set of referencesignals associated with the downlink control channel based at least inpart on the determination of whether at least one reference signalassociated with the second downlink control channel associated with thesecond set of downlink control channel resources is present in theoverlap, as described for example with reference to FIGS. 2-5. Forexample, the set of reference signals associated with the downlinkcontrol channel may be spatially processed when it is determined thatthe at least one reference signal associated with the second downlinkcontrol channel is present in the overlap.

The demodulator 745 may be used to demodulate the downlink controlchannel based at least in part on the set of reference signals, asdescribed for example with reference to FIGS. 2-5. Demodulator 745 maydemodulate one or more downlink control channel candidates of the firstsearch space within the resources of the first control resource set thatoverlap with the resources of the second control resource set based onthe first set of reference signals, where the communicating with thebase station is based on the demodulating. In some cases, the monitoringthe first search space includes: demodulating one or more downlinkcontrol channel candidates of the first search space within theresources of the first control resource set that overlap with theresources of the second control resource set based on the first set ofreference signals.

Search space monitor 750 may identify a first control resource set and asecond control resource set, where resources of the first controlresource set at least partially overlap with resources of the secondcontrol resource set, identify at least one physical channel transmittedon at least a portion of the first control resource set, where adownlink control channel is rate matched around the at least onephysical channel, monitor a second search space of the second controlresource set, where the monitoring the second search space includesrate-matching second downlink control channel resources of the secondcontrol resource set for the second search space independently of thefirst control resource set, communicate with a base station based oncontrol information identified as a result of the monitoring of thefirst search space or the monitoring of the second search space, monitora first search space of the first control resource set, where themonitoring the first search space includes rate-matching first downlinkcontrol channel resources of the first control resource set for thefirst search space independently of the second control resource set,identify a second control resource set, where resources of the firstcontrol resource set at least partially overlap with resources of thesecond control resource set, and where second locations for a second setof reference signals of the second control resource set arenon-coincident with the first locations within the resources of thefirst control resource set that overlap with the resources of the secondcontrol resource set, monitor a first search space of the first controlresource set, where the monitoring the first search space includes ratematching first downlink control channel resources of the first controlresource set around the first locations and the second locations withinthe resources of the first control resource set that overlap with theresources of the second control resource set, communicate with a basestation based on control information identified as a result of themonitoring the first search space, and identify a first control resourceset configured for downlink control information for the UE, the firstcontrol resource set having first locations for a first set of referencesignals. In some cases, the monitoring the first search space includesrate matching the first downlink control channel resources to the secondlocations within the resources of the first control resource set thatoverlap with the resources of the second control resource set. In somecases, the rate matching the first downlink control channel resources tothe second locations is based on a type of the first control resourceset and a type of the second control resource set. In some cases, themonitoring the first search space includes spatially processing theresources of the first control resource set that overlap with theresources of the second control resource set based on the first set ofreference signals.

FIG. 8 shows a block diagram 800 of an apparatus 805 for use in wirelesscommunication, in accordance with various aspects of the presentdisclosure. The apparatus 805 may be an example of aspects of one ormore of the base stations described with reference to FIG. 1. Theapparatus 805 may include a receiver 810, a wireless communicationmanager 815, and a transmitter 820. The apparatus 805 may also include aprocessor. Each of these components may be in communication with oneanother (e.g., via one or more buses).

The receiver 810 may receive data or control signals or information(i.e., transmissions), some or all of which may be associated withvarious information channels (e.g., data channels, control channels,etc.). Received signals or information, or measurements performedthereon, may be passed to other components of the apparatus 805.

The transmitter 820 may transmit data or control signals or information(i.e., transmissions) generated by other components of the apparatus805, some or all of which may be associated with various informationchannels (e.g., data channels, control channels, etc.). In someexamples, the transmitter 820 may be used to transmit a downlink controlchannel and associated set of reference signals. In some examples, thetransmitter 820 may be collocated with the receiver 810 in atransceiver. For example, the transmitter 820 and receiver 810 may be anexample of aspects of the transceiver(s) 1150 described with referenceto FIG. 11.

The wireless communication manager 815 and/or at least some of itsvarious sub-components may be implemented in hardware, software executedby a processor, firmware, or any combination thereof. If implemented insoftware executed by a processor, the functions of the wirelesscommunication manager 815 and/or at least some of its varioussub-components may be executed by a general-purpose processor, a DSP, anASIC, an FPGA or other programmable logic device, discrete gate ortransistor logic, discrete hardware components, or any combinationthereof designed to perform the functions described in the presentdisclosure.

The wireless communication manager 815 and/or at least some of itsvarious sub-components may be physically located at various positions,including being distributed such that portions of functions areimplemented at different physical locations by one or more physicaldevices. In some examples, the wireless communication manager 815 and/orat least some of its various sub-components may be a separate anddistinct component in accordance with various aspects of the presentdisclosure. In other examples, the wireless communication manager 815and/or at least some of its various sub-components may be combined withone or more other hardware components, including but not limited to anI/O component, a transceiver, another computing device, one or moreother components described in the present disclosure, or a combinationthereof, in accordance with various aspects of the present disclosure.The wireless communication manager 815 may include a resource setoverlap identifier 825, a reference signal identifier 830, and atransmission manager 835.

The resource set overlap identifier 825 may be used to identify anoverlap in resources between a first set of downlink control channelresources and a second set of downlink control channel resources, asdescribed for example with reference to FIGS. 2-5. In some examples, thefirst set of downlink control channel resources may be a first searchspace within a downlink control resource set, and the second set ofdownlink control channel resources may be a second search space. Inother examples, the first set of downlink control channel resources maybe a first downlink control resource set and the second set of downlinkcontrol channel resources may be a second downlink control resource set(and in some of these examples, the first downlink control channel maybe further included in a search space of the first downlink controlresource set).

The reference signal identifier 830 may be used to identify, based atleast in part on the overlap, a set of reference signals associated witha downlink control channel for transmission on the first set of downlinkcontrol channel resources, as described for example with reference toFIGS. 2-5.

The transmission manager 835 may be used to transmit the downlinkcontrol channel and the set of reference signals on the first set ofdownlink control channel resources, as described for example withreference to FIGS. 2-5. In some examples, the transmitting may includetransmitting the downlink control channel on a subset of resources ofthe first search space. The subset of resources may be at leastpartially within the overlap.

FIG. 9 shows a block diagram 900 of a wireless communication manager915, in accordance with various aspects of the present disclosure. Thewireless communication manager 915 may be an example of aspects of thewireless communication manager described with reference to FIG. 8. Thewireless communication manager 915 may include a resource set overlapidentifier 925, a reference signal identifier 930, an optional ratematch determiner 935, a transmission manager 940, and an optionalspatial processor 945. Each of these components may communicate,directly or indirectly, with one another (e.g., via one or more buses).The resource set overlap identifier 925, reference signal identifier930, and transmission manager 940 may be examples of the resource setoverlap identifier 825, reference signal identifier 830, andtransmission manager 835 described with reference to FIG. 8.

The resource set overlap identifier 925 may be used to identify anoverlap in resources between a first set of downlink control channelresources and a second set of downlink control channel resources, asdescribed for example with reference to FIGS. 2-5. In some examples, thefirst set of downlink control channel resources may be a first searchspace within a downlink control resource set, and the second set ofdownlink control channel resources may be a second search space withinthe downlink control resource set. In other examples, the first set ofdownlink control channel resources may be a first downlink controlresource set and the second set of downlink control channel resourcesmay be a second downlink control resource set (and in some of theseexamples, the first downlink control channel may be further included ina search space of the first downlink control resource set).

The reference signal identifier 930 may be used to identify, based atleast in part on the overlap, a set of reference signals associated witha downlink control channel for transmission on the first set of downlinkcontrol channel resources, as described for example with reference toFIGS. 2-5. In some examples, identifying the set of reference signalsmay include determining whether to transmit at least one referencesignal in the set of reference signals in the overlap based at least inpart on a type of the first set of downlink control channel resources.

The reference signal identifier 930 may also be used to determinewhether to transmit at least one reference signal associated with asecond downlink control channel associated with the second set ofdownlink control channel resources in the overlap based at least in parton a type of the first set of downlink control channel resources and atype of the second set of downlink control channel resources, asdescribed for example with reference to FIGS. 2-5. In some examples, theat least one reference signal associated with the second downlinkcontrol channel may coincide with a reference signal of the set ofreference signals associated with the downlink control channel.

The rate match determiner 935 may be used to rate matching the downlinkcontrol channel around the set of reference signals. The rate matchdeterminer 935 may also be used to determine whether to rate match thedownlink control channel around at least one reference signal associatedwith a second downlink control channel associated with the second set ofdownlink control channel resources based at least in part on the type ofthe first set of downlink control channel resources and the type of thesecond set of downlink control channel resources, and when applicable,to rate match the downlink control channel around the at least onereference signal associated with the second downlink control channel.The rate match determiner 935 may also be used to identify at least onephysical channel transmitted on at least a portion of the first set ofdownlink control channel resources, and when applicable, to rate matchthe downlink control channel around the at least one physical channel.

The transmission manager 940 may be used to transmit the downlinkcontrol channel and the set of reference signals on the first set ofdownlink control channel resources, as described for example withreference to FIGS. 2-5. In some examples, at least a portion of thedownlink control channel may be transmitted on resources of the firstset of downlink control channel resources within the overlap. In some ofthese examples, the transmitting may include using the spatial processor945 to spatially process the set of reference signals associated withthe downlink control channel based at least in part on the determinationof whether to transmit at least one reference signal associated with asecond downlink control channel associated with the second set ofdownlink control channel resources in the overlap. For example, the setof reference signals associated with the downlink control channel may bespatially processed when it is determined that the at least onereference signal associated with the second downlink control channel tobe transmitted in the overlap. In other examples, the downlink controlchannel may be transmitted on resources of the first set of downlinkcontrol channel resources exclusive of the overlap. In some examples,the transmitting may include transmitting the downlink control channelon a subset of resources of the first search space.

FIG. 10 shows a block diagram 1000 of a UE 1015 for use in wirelesscommunication, in accordance with various aspects of the presentdisclosure. The UE 1015 may be included or be part of a personalcomputer (e.g., a laptop computer, a netbook computer, a tabletcomputer, etc.), a cellular telephone, a PDA, a digital video recorder(DVR), an internet appliance, a gaming console, an e-reader, a vehicle,a home appliance, a lighting or alarm control system, etc. The UE 1015may, in some examples, have an internal power supply (not shown), suchas a small battery, to facilitate mobile operation. In some examples,the UE 1015 may be an example of aspects of one or more of the UEsdescribed with reference to FIG. 1, or aspects of the apparatusdescribed with reference to FIG. 6. The UE 1015 may be configured toimplement at least some of the UE or apparatus techniques or functionsdescribed with reference to FIGS. 1-7.

The UE 1015 may include a processor 1010, a memory 1020, at least onetransceiver (represented by transceiver(s) 1030), antennas 1040 (e.g.,an antenna array), or a wireless communication manager 1050. Each ofthese components may be in communication with each other, directly orindirectly, over one or more buses 1035.

The memory 1020 may include random access memory (RAM) or read-onlymemory (ROM). The memory 1020 may store computer-readable,computer-executable code 1025 containing instructions that areconfigured to, when executed, cause the processor 1010 to performvarious functions described herein related to wireless communication,including, for example, determining whether reference signals fordemodulation of a downlink control channel are present within a regionof overlap between different downlink control resource sets or differentsearch spaces of a same downlink control resource set. Alternatively,the computer-executable code 1025 may not be directly executable by theprocessor 1010 but be configured to cause the UE 1015 (e.g., whencompiled and executed) to perform various of the functions describedherein.

The processor 1010 may include an intelligent hardware device, e.g., acentral processing unit (CPU), a microcontroller, an ASIC, etc. Theprocessor 1010 may process information received through thetransceiver(s) 1030 or information to be sent to the transceiver(s) 1030for transmission through the antennas 1040. The processor 1010 mayhandle, alone or in connection with the wireless communication manager1050, one or more aspects of communicating over (or managingcommunications over) one or more radio frequency spectrum bands.

The transceiver(s) 1030 may include a modem configured to modulatepackets and provide the modulated packets to the antennas 1040 fortransmission, and to demodulate packets received from the antennas 1040.The transceiver(s) 1030 may, in some examples, be implemented as one ormore transmitters and one or more separate receivers. The transceiver(s)1030 may support communications in one or more radio frequency spectrumbands. The transceiver(s) 1030 may be configured to communicatebi-directionally, via the antennas 1040, with one or more base stationsor apparatuses, such as one or more of the base stations or apparatusesdescribed with reference to FIGS. 1 and 8.

The wireless communication manager 1050 may be configured to perform orcontrol some or all of the UE or apparatus techniques or functionsdescribed with reference to FIGS. 1-7. The wireless communicationmanager 1050, or portions of it, may include a processor, or some or allof the functions of the wireless communication manager 1050 may beperformed by the processor 1010 or in connection with the processor1010. In some examples, the wireless communication manager 1050 may bean example of aspects of one or more of the wireless communicationmanagers described with reference to FIGS. 6 and 7.

FIG. 11 shows a block diagram 1100 of a base station 1105 for use inwireless communication, in accordance with various aspects of thepresent disclosure. In some examples, the base station 1105 may be anexample of aspects of one or more of the base stations described withreference to FIG. 1, or aspects of the apparatus described withreference to FIG. 8. The base station 1105 may be configured toimplement or facilitate at least some of the base station or apparatustechniques or functions described with reference to FIGS. 1-5, 8, and 9.

The base station 1105 may include a processor 1110, a memory 1120, atleast one transceiver (represented by transceiver(s) 1150), at least oneantenna 1155 (e.g., an antenna array), or a wireless communicationmanager 1160. The base station 1105 may also include one or more of abase station communicator 1130 or a network communicator 1140. Each ofthese components may be in communication with each other, directly orindirectly, over one or more buses 1135.

The memory 1120 may include RAM or ROM. The memory 1120 may storecomputer-readable, computer-executable code 1125 containing instructionsthat are configured to, when executed, cause the processor 1110 toperform various functions described herein related to wirelesscommunication, including, for example, determining whether to transmitreference signals for a downlink control channel, which referencesignals are within a region of overlap between different downlinkcontrol resource sets or different search spaces of a same downlinkcontrol resource set. Alternatively, the computer-executable code 1125may not be directly executable by the processor 1110 but be configuredto cause the base station 1105 (e.g., when compiled and executed) toperform various of the functions described herein.

The processor 1110 may include an intelligent hardware device, e.g., aCPU, a microcontroller, an ASIC, etc. The processor 1110 may processinformation received through the transceiver(s) 1150, the base stationcommunicator 1130, or the network communicator 1140. The processor 1110may also process information to be sent to the transceiver(s) 1150 fortransmission through the antennas 1155, or to the base stationcommunicator 1130 for transmission to one or more other base stations(e.g., base station 1105-a and base station 1105-b), or to the networkcommunicator 1140 for transmission to a core network 1145, which may bean example of one or more aspects of the core network 130 described withreference to FIG. 1. The processor 1110 may handle, alone or inconnection with the wireless communication manager 1160, one or moreaspects of communicating over (or managing communications over) one ormore radio frequency spectrum bands.

The transceiver(s) 1150 may include a modem configured to modulatepackets and provide the modulated packets to the antennas 1155 fortransmission, and to demodulate packets received from the antennas 1155.The transceiver(s) 1150 may, in some examples, be implemented as one ormore transmitters and one or more separate receivers. The transceiver(s)1150 may support communications in one or more radio frequency spectrumbands. The transceiver(s) 1150 may be configured to communicatebi-directionally, via the antennas 1155, with one or more UEs orapparatuses, such as one or more of the UEs or apparatus described withreference to FIGS. 1, 6, and 9. The base station 1105 may communicatewith the core network 1145 through the network communicator 1140. Thebase station 1105 may also communicate with other base stations, such asthe base station 1105-a and the base station 1105-b, using the basestation communicator 1130.

The wireless communication manager 1160 may be configured to perform orcontrol some or all of the base station or apparatus techniques orfunctions described with reference to FIGS. 1-5, 8, and 9. The wirelesscommunication manager 1160, or portions of it, may include a processor,or some or all of the functions of the wireless communication manager1160 may be performed by the processor 1110 or in connection with theprocessor 1110. In some examples, the wireless communication manager1160 may be an example of aspects of one or more of the wirelesscommunication managers described with reference to FIGS. 8 and 9.

FIG. 12 is a flow chart illustrating an example of a method 1200 forwireless communication at a UE, in accordance with various aspects ofthe present disclosure. For clarity, the method 1200 is described belowwith reference to aspects of one or more of the UEs described withreference to FIGS. 1 and 10, aspects of the apparatus described withreference to FIG. 6, or aspects of one or more of the wirelesscommunication managers described with reference to FIGS. 6, 7, and 10.In some examples, a UE may execute one or more sets of codes to controlthe functional elements of the UE to perform the functions describedbelow. Additionally or alternatively, the UE may perform one or more ofthe functions described below using special-purpose hardware.

At block 1205, the method 1200 may include identifying an overlap inresources between a first set of downlink control channel resourcesincluding a downlink control channel, and a second set of downlinkcontrol channel resources, as described for example with reference toFIGS. 2-5. In some examples, the first set of downlink control channelresources may be a first search space within a first downlink controlresource set, and the second set of downlink control channel resourcesmay be a second search space within the first downlink control resourceset or a second downlink control resource set. In other examples, thefirst set of downlink control channel resources may be a first downlinkcontrol resource set and the second set of downlink control channelresources may be a second downlink control resource set (and in some ofthese examples, the first downlink control channel may be furtherincluded in a search space of the first downlink control resource set).In some examples, the operation(s) at block 1205 may be performed usingthe resource set overlap identifier described with reference to FIGS. 6and 7.

At block 1210, the method 1200 may include identifying, based at leastin part on the overlap, a set of reference signals associated with thedownlink control channel, as described for example with reference toFIGS. 2-5. In some examples, the operation(s) at block 1210 may beperformed using the reference signal identifier described with referenceto FIGS. 6 and 7.

At block 1215, the method 1200 may optionally include receiving thedownlink control channel on a subset of resources of the first searchspace (e.g., when the identified overlap is between the first searchspace and the second search space), as described for example withreference to FIGS. 2-5. In some examples, the operation(s) at block 1215may be performed using the receiver described with reference to FIG. 6.

At block 1220, the method 1200 may include demodulating the downlinkcontrol channel based at least in part on the set of reference signals,as described for example with reference to FIGS. 2-5. In some examples,the operation(s) at block 1220 may be performed using the demodulatordescribed with reference to FIGS. 6 and 7.

FIG. 13 is a flow chart illustrating an example of a method 1300 forwireless communication at a UE, in accordance with various aspects ofthe present disclosure. For clarity, the method 1300 is described belowwith reference to aspects of one or more of the UEs described withreference to FIGS. 1 and 10, aspects of the apparatus described withreference to FIG. 6, or aspects of one or more of the wirelesscommunication managers described with reference to FIGS. 6, 7, and 10.In some examples, a UE may execute one or more sets of codes to controlthe functional elements of the UE to perform the functions describedbelow. Additionally or alternatively, the UE may perform one or more ofthe functions described below using special-purpose hardware.

At block 1305, the method 1300 may include identifying an overlap inresources between a first set of downlink control channel resourcesincluding a downlink control channel, and a second set of downlinkcontrol channel resources, as described for example with reference toFIGS. 2-5. In some examples, the first set of downlink control channelresources may be a first search space within a downlink control resourceset, and the second set of downlink control channel resources may be asecond search space within the first downlink control resource set or asecond downlink control resource set. In other examples, the first setof downlink control channel resources may be a first downlink controlresource set and the second set of downlink control channel resourcesmay be a second downlink control resource set (and in some of theseexamples, the first downlink control channel may be further included ina search space of the first downlink control resource set). In someexamples, the operation(s) at block 1305 may be performed using theresource set overlap identifier described with reference to FIGS. 6 and7.

At block 1310, the method 1300 may include identifying, based at leastin part on the overlap, a set of reference signals associated with thedownlink control channel, as described for example with reference toFIGS. 2-5. In some examples, the operation(s) at block 1310 may beperformed using the reference signal identifier described with referenceto FIGS. 6 and 7.

The method 1300 may optionally include the operation(s) at one or moreof blocks 1315, 1320, or 1325. At block 1315, the method 1300 mayoptionally include determining whether the downlink control channel israte matched around at least one reference signal associated with asecond downlink control channel associated with the second set ofdownlink control channel resources, as described for example withreference to FIGS. 2-5. The determination may be based at least in parton a type of the first set of downlink control channel resources and atype of the second set of downlink control channel resources. In someexamples, the operation(s) at block 1315 may be performed using the ratematch determiner described with reference to FIG. 7.

At block 1320, the method 1300 may optionally include identifying atleast one physical channel transmitted on at least a portion of thefirst set of downlink control channel resources, as described forexample with reference to FIGS. 2-5. In some examples, the operation(s)at block 1320 may be performed using the rate match determiner describedwith reference to FIG. 7.

At block 1325, the method 1300 may optionally include determiningwhether at least one reference signal associated with the seconddownlink control channel associated with the second set of downlinkcontrol channel resources is present in the overlap, as described forexample with reference to FIGS. 2-5. The determination may be based atleast in part on the type of the first set of downlink control channelresources and the type of the second set of downlink control channelresources. In some examples, the at least one reference signalassociated with the second downlink control channel may coincide with areference signal of the set of reference signals associated with thedownlink control channel. In some examples, the operation(s) at block1325 may be performed using the reference signal identifier describedwith reference to FIGS. 6 and 7.

At block 1330, the method 1300 may include receiving at least a portionof the downlink control channel on resources of the first set ofdownlink control channel resources within the overlap, as described forexample with reference to FIGS. 2-5. In some examples, the downlinkcontrol channel may be rate matched around the set of reference signals.The downlink control channel may also or alternatively be rate matchedaround the at least one reference signal associated with the seconddownlink control channel or the at least one physical channel. In someexamples, the operation(s) at block 1330 may be performed using thereceiver described with reference to FIG. 6.

At block 1335, and when the method includes the operations at block1325, the method 1300 may optionally include spatially processing theset of reference signals associated with the downlink control channelbased at least in part on the determination made at block 1325, asdescribed for example with reference to FIGS. 2-5. For example, the setof reference signals associated with the downlink control channel may bespatially processed when it is determined that the at least onereference signal associated with the second downlink control channel ispresent in the overlap. In some examples, the operation(s) at block 1335may be performed using the spatial processor described with reference toFIG. 7.

At block 1340, the method 1300 may include demodulating the downlinkcontrol channel based at least in part on the set of reference signals,as described for example with reference to FIGS. 2-5. In some examples,the operation(s) at block 1340 may be performed using the demodulatordescribed with reference to FIGS. 6 and 7.

FIG. 14 is a flow chart illustrating an example of a method 1400 forwireless communication at a UE, in accordance with various aspects ofthe present disclosure. For clarity, the method 1400 is described belowwith reference to aspects of one or more of the UEs described withreference to FIGS. 1 and 10, aspects of the apparatus described withreference to FIG. 6, or aspects of one or more of the wirelesscommunication managers described with reference to FIGS. 6, 7, and 10.In some examples, a UE may execute one or more sets of codes to controlthe functional elements of the UE to perform the functions describedbelow. Additionally or alternatively, the UE may perform one or more ofthe functions described below using special-purpose hardware.

At block 1405, the method 1400 may include identifying an overlap inresources between a first set of downlink control channel resourcesincluding a downlink control channel, and a second set of downlinkcontrol channel resources, as described for example with reference toFIGS. 2-5. In some examples, the first set of downlink control channelresources may be a first search space within a first downlink controlresource set, and the second set of downlink control channel resourcesmay be a second search space within the first downlink control resourceset or a second downlink control resource set. In other examples, thefirst set of downlink control channel resources may be a first downlinkcontrol resource set and the second set of downlink control channelresources may be a second downlink control resource set (and in some ofthese examples, the first downlink control channel may be furtherincluded in a search space of the first downlink control resource set).In some examples, the operation(s) at block 1405 may be performed usingthe resource set overlap identifier described with reference to FIGS. 6and 7.

At block 1410, the method 1400 may include identifying, based at leastin part on the overlap, a set of reference signals associated with thedownlink control channel, as described for example with reference toFIGS. 2-5. In some examples, identifying the set of reference signalsmay include determining whether at least one reference signal in the setof reference signals is located in the overlap based at least in part ona type of the first set of downlink control channel resources. In someexamples, the operation(s) at block 1410 may be performed using thereference signal identifier described with reference to FIGS. 6 and 7.

At block 1415, the method 1400 may include receiving the downlinkcontrol channel on resources of the first set of downlink controlchannel resources exclusive of the overlap, as described for examplewith reference to FIGS. 2-5. In some examples, the operation(s) at block1415 may be performed using the receiver described with reference toFIG. 6.

At block 1420, the method 1400 may include demodulating the downlinkcontrol channel based at least in part on the set of reference signals,as described for example with reference to FIGS. 2-5. In some examples,the operation(s) at block 1420 may be performed using the demodulatordescribed with reference to FIGS. 6 and 7.

FIG. 15 is a flow chart illustrating an example of a method 1500 forwireless communication at a base station, in accordance with variousaspects of the present disclosure. For clarity, the method 1500 isdescribed below with reference to aspects of one or more of the basestations described with reference to FIGS. 1 and 11, aspects of theapparatus described with reference to FIG. 8, or aspects of one or moreof the wireless communication managers described with reference to FIGS.8, 9, and 11. In some examples, a base station may execute one or moresets of codes to control the functional elements of the base station toperform the functions described below. Additionally or alternatively,the base station may perform one or more of the functions describedbelow using special-purpose hardware.

At block 1505, the method 1500 may include identifying an overlap inresources between a first set of downlink control channel resources anda second set of downlink control channel resources, as described forexample with reference to FIGS. 2-5. In some examples, the first set ofdownlink control channel resources may be a first search space within afirst downlink control resource set, and the second set of downlinkcontrol channel resources may be a second search space within the firstdownlink control resource set or a second downlink control resource set.In other examples, the first set of downlink control channel resourcesmay be a first downlink control resource set and the second set ofdownlink control channel resources may be a second downlink controlresource set (and in some of these examples, the first downlink controlchannel may be further included in a search space of the first downlinkcontrol resource set). In some examples, the operation(s) at block 1505may be performed using the resource set overlap identifier describedwith reference to FIGS. 8 and 9.

At block 1510, the method 1500 may include identifying, based at leastin part on the overlap, a set of reference signals associated with adownlink control channel for transmission on the first set of downlinkcontrol channel resources, as described for example with reference toFIGS. 2-5. In some examples, the operation(s) at block 1510 may beperformed using the reference signal identifier described with referenceto FIGS. 8 and 9.

At block 1515, the method 1500 may include transmitting the downlinkcontrol channel and the set of reference signals on the first set ofdownlink control channel resources, as described for example withreference to FIGS. 2-5. In some examples, the transmitting may includetransmitting the downlink control channel on a subset of resources ofthe first search space. In some examples, the operation(s) at block 1515may be performed using the transmission manager described with referenceto FIGS. 8 and 9.

FIG. 16 is a flow chart illustrating an example of a method 1600 forwireless communication at a base station, in accordance with variousaspects of the present disclosure. For clarity, the method 1600 isdescribed below with reference to aspects of one or more of the basestations described with reference to FIGS. 1 and 11, aspects of theapparatus described with reference to FIG. 8, or aspects of one or moreof the wireless communication managers described with reference to FIGS.8, 9, and 11. In some examples, a base station may execute one or moresets of codes to control the functional elements of the base station toperform the functions described below. Additionally or alternatively,the base station may perform one or more of the functions describedbelow using special-purpose hardware.

At block 1605, the method 1600 may include identifying an overlap inresources between a first set of downlink control channel resources anda second set of downlink control channel resources, as described forexample with reference to FIGS. 2-5. In some examples, the first set ofdownlink control channel resources may be a first search space within afirst downlink control resource set, and the second set of downlinkcontrol channel resources may be a second search space within the firstdownlink control resource set or a second downlink control resource set.In other examples, the first set of downlink control channel resourcesmay be a first downlink control resource set and the second set ofdownlink control channel resources may be a second downlink controlresource set (and in some of these examples, the first downlink controlchannel may be further included in a search space of the first downlinkcontrol resource set). In some examples, the operation(s) at block 1605may be performed using the resource set overlap identifier describedwith reference to FIGS. 8 and 9.

At block 1610, the method 1600 may optionally include determiningwhether to transmit at least one reference signal associated with asecond downlink control channel associated with the second set ofdownlink control channel resources in the overlap based at least in parton a type of the first set of downlink control channel resources and atype of the second set of downlink control channel resources, asdescribed for example with reference to FIGS. 2-5. In some examples, theat least one reference signal associated with the second downlinkcontrol channel may coincide with a reference signal of the set ofreference signals associated with the downlink control channel. In someexamples, the operation(s) at block 1610 may be performed using thereference signal identifier described with reference to FIGS. 8 and 9.

At block 1615, the method 1600 may include identifying, based at leastin part on the overlap, a set of reference signals associated with adownlink control channel for transmission on the first set of downlinkcontrol channel resources, as described for example with reference toFIGS. 2-5. In some examples, the operation(s) at block 1615 may beperformed using reference signal identifier described with reference toFIGS. 8 and 9.

The method 1600 may optionally include the operation(s) at one or moreof blocks 1620 or 1625. At block 1620, the method 1600 may optionallyinclude determining whether to rate match the downlink control channelaround at least one reference signal associated with a second downlinkcontrol channel associated with the second set of downlink controlchannel resources based at least in part on the type of the first set ofdownlink control channel resources and the type of the second set ofdownlink control channel resources. In some examples, the operation(s)at block 1620 may be performed using rate match determiner describedwith reference to FIG. 9.

At block 1625, the method 1600 may optionally include identifying atleast one physical channel transmitted on at least a portion of thefirst set of downlink control channel resources. In some examples, theoperation(s) at block 1625 may be performed using rate match determinerdescribed with reference to FIG. 9.

At block 1630, the method 1600 may include rate matching the downlinkcontrol channel around the set of reference signals. In some examples,the method 1600 may also include rate matching the downlink controlchannel around the at least one reference signal associated with thesecond downlink control channel or the at least one physical channel. Insome examples, the operation(s) at block 1630 may be performed usingrate match determiner described with reference to FIG. 9.

At block 1635, the method 1600 may include transmitting the downlinkcontrol channel and the set of reference signals on the first set ofdownlink control channel resources, as described for example withreference to FIGS. 2-5. At least a portion of the downlink controlchannel may be transmitted on resources of the first set of downlinkcontrol channel resources within the overlap. In some examples, thetransmitting may include spatially processing the set of referencesignals associated with the downlink control channel based at least inpart on the determination made at block 1610. For example, the set ofreference signals associated with the downlink control channel may bespatially processed when it is determined that the at least onereference signal associated with the second downlink control channel tobe transmitted in the overlap. In some examples, the transmitting mayinclude transmitting the downlink control channel on a subset ofresources of the first search space. In some examples, the operation(s)at block 1635 may be performed using the transmission manager describedwith reference to FIGS. 8 and 9.

FIG. 17 is a flow chart illustrating an example of a method 1700 forwireless communication at a base station, in accordance with variousaspects of the present disclosure. For clarity, the method 1700 isdescribed below with reference to aspects of one or more of the basestations described with reference to FIGS. 1 and 11, aspects of theapparatus described with reference to FIG. 8, or aspects of one or moreof the wireless communication managers described with reference to FIGS.8, 9, and 11. In some examples, a base station may execute one or moresets of codes to control the functional elements of the base station toperform the functions described below. Additionally or alternatively,the base station may perform one or more of the functions describedbelow using special-purpose hardware.

At block 1705, the method 1700 may include identifying an overlap inresources between a first set of downlink control channel resources anda second set of downlink control channel resources, as described forexample with reference to FIGS. 2-5. In some examples, the first set ofdownlink control channel resources may be a first search space within adownlink control resource set, and the second set of downlink controlchannel resources may be a second search space within the downlinkcontrol resource set. In other examples, the first set of downlinkcontrol channel resources may be a first downlink control resource setand the second set of downlink control channel resources may be a seconddownlink control resource set (and in some of these examples, the firstdownlink control channel may be further included in a search space ofthe first downlink control resource set). In some examples, theoperation(s) at block 1705 may be performed using the resource setoverlap identifier described with reference to FIGS. 8 and 9.

At block 1710, the method 1700 may include identifying, based at leastin part on the overlap, a set of reference signals associated with adownlink control channel for transmission on the first set of downlinkcontrol channel resources, as described for example with reference toFIGS. 2-5. In some examples, identifying the set of reference signalsmay include determining whether to transmit at least one referencesignal in the set of reference signals in the overlap based at least inpart on a type of the first set of downlink control channel resources.In some examples, the operation(s) at block 1710 may be performed usingreference signal identifier described with reference to FIGS. 8 and 9.

At block 1715, the method 1700 may include transmitting the downlinkcontrol channel and the set of reference signals on the first set ofdownlink control channel resources, as described for example withreference to FIGS. 2-5. The downlink control channel may be transmittedon resources of the first set of downlink control channel resourcesexclusive of the overlap. In some examples, the transmitting may includetransmitting the downlink control channel on a subset of resources ofthe first search space. In some examples, the operation(s) at block 1715may be performed using the transmission manager described with referenceto FIGS. 8 and 9.

FIG. 18 shows a flowchart illustrating a method 1800 for techniques forhandling overlapping sets of downlink control channel resources inaccordance with aspects of the present disclosure. The operations ofmethod 1800 may be implemented by a UE 115 or its components asdescribed herein. For clarity, the method 1800 is described below withreference to aspects of one or more of the UEs described with referenceto FIGS. 1 and 10, aspects of the apparatus described with reference toFIG. 6, or aspects of one or more of the wireless communication managersdescribed with reference to FIGS. 6, 7, and 10. In some examples, a UEmay execute one or more sets of codes to control the functional elementsof the UE to perform the functions described below. Additionally oralternatively, the UE may perform one or more of the functions describedbelow using special-purpose hardware.

At block 1805, the method 1800 may include identifying a first controlresource set and a second control resource set, wherein resources of thefirst control resource set at least partially overlap with resources ofthe second control resource set, as described for example with referenceto FIGS. 2-5. The operations of 1805 may be performed according to themethods described herein. In certain examples, aspects of the operationsof 1805 may be performed by a search space monitor as described withreference to FIGS. 6 and 7.

At block 1810, the method 1800 may include monitoring a first searchspace of the first control resource set, wherein the monitoring thefirst search space comprises rate-matching first downlink controlchannel resources of the first control resource set for the first searchspace independently of the second control resource set, as described forexample with reference to FIGS. 2-5. The operations of 1810 may beperformed according to the methods described herein. In certainexamples, aspects of the operations of 1810 may be performed by a searchspace monitor as described with reference to FIGS. 6 and 7.

At block 1815, the method 1800 may include monitoring a second searchspace of the second control resource set, wherein the monitoring thesecond search space comprises rate-matching second downlink controlchannel resources of the second control resource set for the secondsearch space independently of the first control resource set, asdescribed for example with reference to FIGS. 2-5. The operations of1815 may be performed according to the methods described herein. Incertain examples, aspects of the operations of 1815 may be performed bya search space monitor as described with reference to FIGS. 6 and 7.

At block 1820, the method 1800 may include communicating with a basestation based at least in part on control information identified as aresult of the monitoring of the first search space or the monitoring ofthe second search space, as described for example with reference toFIGS. 2-5. The operations of 1820 may be performed according to themethods described herein. In certain examples, aspects of the operationsof 1820 may be performed by a search space monitor as described withreference to FIGS. 6 and 7.

FIG. 19 shows a flowchart illustrating a method 1900 for techniques forhandling overlapping sets of downlink control channel resources inaccordance with aspects of the present disclosure. The operations ofmethod 1900 may be implemented by a UE 115 or its components asdescribed herein. For clarity, the method 1900 is described below withreference to aspects of one or more of the UEs described with referenceto FIGS. 1 and 10, aspects of the apparatus described with reference toFIG. 6, or aspects of one or more of the wireless communication managersdescribed with reference to FIGS. 6, 7, and 10. In some examples, a UEmay execute one or more sets of codes to control the functional elementsof the UE to perform the functions described below. Additionally oralternatively, the UE may perform one or more of the functions describedbelow using special-purpose hardware.

At block 1905, the method 1900 may include identifying a first controlresource set and a second control resource set, wherein resources of thefirst control resource set at least partially overlap with resources ofthe second control resource set, as described for example with referenceto FIGS. 2-5. The operations of 1905 may be performed according to themethods described herein. In certain examples, aspects of the operationsof 1905 may be performed by a search space monitor as described withreference to FIGS. 6 and 7.

At block 1910, the method 1900 may include identifying first locationsfor a first set of reference signals associated with the first controlresource set, as described for example with reference to FIGS. 2-5. Theoperations of 1910 may be performed according to the methods describedherein. In certain examples, aspects of the operations of 1910 may beperformed by a reference signal identifier as described with referenceto FIGS. 6 and 7.

At block 1915, the method 1900 may include monitoring a first searchspace of the first control resource set, wherein the monitoring thefirst search space comprises rate-matching first downlink controlchannel resources of the first control resource set for the first searchspace independently of the second control resource set and rate matchingthe first downlink control channel resources around the first locations,as described for example with reference to FIGS. 2-5. The operations of1915 may be performed according to the methods described herein. Incertain examples, aspects of the operations of 1915 may be performed bya search space monitor as described with reference to FIGS. 6 through 7.

At block 1920, the method 1900 may include identifying second locationsfor a second set of reference signals associated with the second controlresource set, as described for example with reference to FIGS. 2-5. Theoperations of 1920 may be performed according to the methods describedherein. In certain examples, aspects of the operations of 1920 may beperformed by a reference signal identifier as described with referenceto FIGS. 6 and 7.

At block 1925, the method 1900 may include monitoring a second searchspace of the second control resource set, wherein the monitoring thesecond search space comprises rate-matching second downlink controlchannel resources of the second control resource set for the secondsearch space independently of the first control resource set and ratematching the second downlink control channel resources around the secondlocations, as described for example with reference to FIGS. 2-5. Theoperations of 1925 may be performed according to the methods describedherein. In certain examples, aspects of the operations of 1925 may beperformed by a search space monitor as described with reference to FIGS.6 and 7.

At block 1930, the method 1900 may include communicating with a basestation based at least in part on control information identified as aresult of the monitoring of the first search space or the monitoring ofthe second search space, as described for example with reference toFIGS. 2-5. The operations of 1930 may be performed according to themethods described herein. In certain examples, aspects of the operationsof 1930 may be performed by a search space monitor as described withreference to FIGS. 6 and 7.

FIG. 20 shows a flowchart illustrating a method 2000 for techniques forhandling overlapping sets of downlink control channel resources inaccordance with aspects of the present disclosure. The operations ofmethod 2000 may be implemented by a UE 115 or its components asdescribed herein. For clarity, the method 2000 is described below withreference to aspects of one or more of the UEs described with referenceto FIGS. 1 and 10, aspects of the apparatus described with reference toFIG. 6, or aspects of one or more of the wireless communication managersdescribed with reference to FIGS. 6, 7, and 10. In some examples, a UEmay execute one or more sets of codes to control the functional elementsof the UE to perform the functions described below. Additionally oralternatively, the UE may perform one or more of the functions describedbelow using special-purpose hardware.

At block 2005, the method 2000 may include identifying a first controlresource set configured for downlink control information for the UE, thefirst control resource set having first locations for a first set ofreference signals, as described for example with reference to FIGS. 2-5.The operations of 2005 may be performed according to the methodsdescribed herein. In certain examples, aspects of the operations of 2005may be performed by a search space monitor as described with referenceto FIGS. 6 and 7.

At block 2010, the method 2000 may include identifying a second controlresource set, wherein resources of the first control resource set atleast partially overlap with resources of the second control resourceset, and wherein second locations for a second set of reference signalsof the second control resource set are non-coincident with the firstlocations within the resources of the first control resource set thatoverlap with the resources of the second control resource set, asdescribed for example with reference to FIGS. 2-5. The operations of2010 may be performed according to the methods described herein. Incertain examples, aspects of the operations of 2010 may be performed bya search space monitor as described with reference to FIGS. 6 and 7.

At block 2015, the method 2000 may include monitoring a first searchspace of the first control resource set, wherein the monitoring thefirst search space comprises rate matching first downlink controlchannel resources of the first control resource set around the firstlocations and the second locations within the resources of the firstcontrol resource set that overlap with the resources of the secondcontrol resource set, as described for example with reference to FIGS.2-5. The operations of 2015 may be performed according to the methodsdescribed herein. In certain examples, aspects of the operations of 2015may be performed by a search space monitor as described with referenceto FIGS. 6 and 7.

At block 2020, the method 2000 may include communicating with a basestation based at least in part on control information identified as aresult of the monitoring the first search space, as described forexample with reference to FIGS. 2-5. The operations of 2020 may beperformed according to the methods described herein. In certainexamples, aspects of the operations of 2020 may be performed by a searchspace monitor as described with reference to FIGS. 6 and 7.

The methods 1200, 1300, 1400, 1500, 1600, 1700, 1800, 1900, and 200described with reference to FIGS. 12-20 are example implementations ofsome of the techniques described in the present disclosure, and theoperations of the methods may be rearranged, combined with otheroperations of the same or different method, or otherwise modified, suchthat other implementations are possible. In some examples, operations ofthe methods 1200, 1300, 1400, 1800, 1900, or 2000 may be combined. Insome examples, operations of the methods 1500, 1600, or 1700 may becombined. In some examples, operations may be added to the methods.

Techniques described herein may be used for various wirelesscommunication systems such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, andother systems. The terms “system” and “network” are often usedinterchangeably. A CDMA system may implement a radio technology such asCDMA2000, Universal Terrestrial Radio Access (UTRA), etc. CDMA2000covers IS-2000, IS-95, and IS-856 standards. IS-2000 Releases 0 and Amay be referred to as CDMA2000 1×, 1×, etc. IS-856 (TIA-856) may bereferred to as CDMA2000 1×EV-DO, High Rate Packet Data (HRPD), etc. UTRAincludes Wideband CDMA (WCDMA) and other variants of CDMA. A TDMA systemmay implement a radio technology such as Global System for MobileCommunications (GSM). An OFDMA system may implement a radio technologysuch as Ultra Mobile Broadband (UMB), Evolved UTRA (E-UTRA), IEEE 802.11(Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDM™, etc. UTRA andE-UTRA are part of Universal Mobile Telecommunication System (UMTS).3GPP LTE and LTE-A are new releases of UMTS that use E-UTRA. UTRA,E-UTRA, UMTS, LTE, LTE-A, and GSM are described in documents from anorganization named 3GPP. CDMA2000 and UMB are described in documentsfrom an organization named “3rd Generation Partnership Project 2”(3GPP2). The techniques described herein may be used for the systems andradio technologies mentioned above as well as other systems and radiotechnologies, including cellular (e.g., LTE) communications over anunlicensed or shared bandwidth. The description above, however,describes an LTE/LTE-A system for purposes of example, and LTEterminology is used in much of the description above, although thetechniques are applicable beyond LTE/LTE-A applications.

The detailed description set forth above in connection with the appendeddrawings describes examples and does not represent all of the examplesthat may be implemented or that are within the scope of the claims. Theterms “example” and “exemplary,” when used in this description, mean“serving as an example, instance, or illustration,” and not “preferred”or “advantageous over other examples.” The detailed description includesspecific details for the purpose of providing an understanding of thedescribed techniques. These techniques, however, may be practicedwithout these specific details. In some instances, well-known structuresand apparatuses are shown in block diagram form in order to avoidobscuring the concepts of the described examples.

Information and signals may be represented using any of a variety ofdifferent technologies and techniques. For example, data, instructions,commands, information, signals, bits, symbols, and chips that may bereferenced throughout the above description may be represented byvoltages, currents, electromagnetic waves, magnetic fields or particles,optical fields or particles, or any combination thereof.

The various illustrative blocks and components described in connectionwith the disclosure herein may be implemented or performed with ageneral-purpose processor, a digital signal processor (DSP), an ASIC, anFPGA or other programmable logic device, discrete gate or transistorlogic, discrete hardware components, or any combination thereof designedto perform the functions described herein. A general-purpose processormay be a microprocessor, but in the alternative, the processor may beany conventional processor, controller, microcontroller, or statemachine. A processor may also be implemented as a combination ofcomputing devices, e.g., a combination of a DSP and a microprocessor,multiple microprocessors, one or more microprocessors in conjunctionwith a DSP core, or any other such configuration.

The functions described herein may be implemented in hardware, softwareexecuted by a processor, firmware, or any combination thereof. Ifimplemented in software executed by a processor, the functions may bestored on or transmitted over as one or more instructions or code on acomputer-readable medium. Other examples and implementations are withinthe scope and spirit of the disclosure and appended claims. For example,due to the nature of software, functions described above can beimplemented using software executed by a processor, hardware, firmware,hardwiring, or combinations of any of these. Components implementingfunctions may also be physically located at various positions, includingbeing distributed such that portions of functions are implemented atdifferent physical locations. As used herein, including in the claims,the term “or,” when used in a list of two or more items, means that anyone of the listed items can be employed by itself, or any combination oftwo or more of the listed items can be employed. For example, if acomposition is described as containing components A, B, or C, thecomposition can contain A alone; B alone; C alone; A and B incombination; A and C in combination; B and C in combination; or A, B,and C in combination. Also, as used herein, including in the claims,“or” as used in a list of items (for example, a list of items prefacedby a phrase such as “at least one of” or “one or more of”) indicates adisjunctive list such that, for example, a list of “at least one of A,B, or C” means A or B or C or AB or AC or BC or ABC (i.e., A and B andC).

Computer-readable media includes both computer storage media andcommunication media including any medium that facilitates transfer of acomputer program from one place to another. A storage medium may be anyavailable medium that can be accessed by a general purpose or specialpurpose computer. By way of example, and not limitation,computer-readable media can include RAM, ROM, EEPROM, flash memory,CD-ROM or other optical disk storage, magnetic disk storage or othermagnetic storage devices, or any other medium that can be used to carryor store desired program code means in the form of instructions or datastructures and that can be accessed by a general-purpose orspecial-purpose computer, or a general-purpose or special-purposeprocessor. Also, any connection is properly termed a computer-readablemedium. For example, if the software is transmitted from a website,server, or other remote source using a coaxial cable, fiber optic cable,twisted pair, digital subscriber line (DSL), or wireless technologiessuch as infrared, radio, and microwave, then the coaxial cable, fiberoptic cable, twisted pair, DSL, or wireless technologies such asinfrared, radio, and microwave are included in the definition of medium.Disk and disc, as used herein, include compact disc (CD), laser disc,optical disc, digital versatile disc (DVD), floppy disk and Blu-ray discwhere disks usually reproduce data magnetically, while discs reproducedata optically with lasers. Combinations of the above are also includedwithin the scope of computer-readable media.

The previous description of the disclosure is provided to enable aperson skilled in the art to make or use the disclosure. Variousmodifications to the disclosure will be readily apparent to thoseskilled in the art, and the generic principles defined herein may beapplied to other variations without departing from the scope of thedisclosure. Thus, the disclosure is not to be limited to the examplesand designs described herein but is to be accorded the broadest scopeconsistent with the principles and novel techniques disclosed herein.

What is claimed is:
 1. A method for wireless communication at a userequipment (UE), comprising: identifying a first control resource set anda second control resource set, wherein resources of the first controlresource set at least partially overlap with resources of the secondcontrol resource set; monitoring a first search space of the firstcontrol resource set, wherein the monitoring the first search spacecomprises rate-matching first downlink control channel resources of thefirst control resource set for the first search space independently ofthe second control resource set; monitoring a second search space of thesecond control resource set, wherein the monitoring the second searchspace comprises rate-matching second downlink control channel resourcesof the second control resource set for the second search spaceindependently of the first control resource set; and communicating witha base station based at least in part on control information identifiedas a result of the monitoring of the first search space or themonitoring of the second search space.
 2. The method of claim 1, furthercomprising: identifying first locations for a first set of referencesignals associated with the first control resource set, wherein themonitoring the first search space comprises rate matching the firstdownlink control channel resources around the first locations.
 3. Themethod of claim 2, further comprising: identifying second locations fora second set of reference signals associated with the second controlresource set, wherein the monitoring the second search space comprisesrate matching the second downlink control channel resources around thesecond locations.
 4. The method of claim 3, wherein the first locationscoincide with the second locations within the resources of the firstcontrol resource set that overlap with the resources of the secondcontrol resource set.
 5. The method of claim 3, wherein the firstlocations are non-coincident with the second locations within theresources of the first control resource set that overlap with theresources of the second control resource set.
 6. The method of claim 5,wherein the monitoring the first search space comprises: rate matchingthe first downlink control channel resources to the second locationswithin the resources of the first control resource set that overlap withthe resources of the second control resource set.
 7. The method of claim6, wherein the rate matching the first downlink control channelresources to the second locations is based at least in part on a type ofthe first control resource set and a type of the second control resourceset.
 8. The method of claim 2, wherein the monitoring the first searchspace comprises: demodulating one or more downlink control channelcandidates of the first search space within the resources of the firstcontrol resource set that overlap with the resources of the secondcontrol resource set based at least in part on the first set ofreference signals.
 9. The method of claim 1, further comprising:determining that at least one reference signal associated with the firstcontrol resource set is in a portion of resources that overlap with thesecond control resource set based at least in part on a type of thefirst control resource set and a type of the second control resourceset.
 10. A method for wireless communication at a user equipment (UE),comprising: identifying a first control resource set configured fordownlink control information for the UE, the first control resource sethaving first locations for a first set of reference signals; identifyinga second control resource set, wherein resources of the first controlresource set at least partially overlap with resources of the secondcontrol resource set, and wherein second locations for a second set ofreference signals of the second control resource set are non-coincidentwith the first locations within the resources of the first controlresource set that overlap with the resources of the second controlresource set; monitoring a first search space of the first controlresource set, wherein the monitoring the first search space comprisesrate matching first downlink control channel resources of the firstcontrol resource set around the first locations and the second locationswithin the resources of the first control resource set that overlap withthe resources of the second control resource set; and communicating witha base station based at least in part on control information identifiedas a result of the monitoring the first search space.
 11. The method ofclaim 10, further comprising: demodulating one or more downlink controlchannel candidates of the first search space within the resources of thefirst control resource set that overlap with the resources of the secondcontrol resource set based at least in part on the first set ofreference signals, wherein the communicating with the base station isbased at least in part on the demodulating.
 12. The method of claim 10,further comprising: determining that at least one reference signalassociated with the first control resource set is in a portion ofresources that overlap with the second control resource set based atleast in part on a type of the first control resource set and a type ofthe second control resource set.
 13. The method of claim 12, wherein themonitoring the first search space comprises: spatially processing theresources of the first control resource set that overlap with theresources of the second control resource set based at least in part onthe first set of reference signals.
 14. The method of claim 10, furthercomprising: identifying at least one physical channel transmitted on atleast a portion of the first control resource set, wherein a downlinkcontrol channel is rate matched around the at least one physicalchannel.
 15. An apparatus for wireless communication, comprising: aprocessor; memory in electronic communication with the processor; andinstructions stored in the memory and executable by the processor tocause the apparatus to: identify a first control resource set and asecond control resource set, wherein resources of the first controlresource set at least partially overlap with resources of the secondcontrol resource set; monitor a first search space of the first controlresource set, wherein the monitoring the first search space comprisesrate-matching first downlink control channel resources of the firstcontrol resource set for the first search space independently of thesecond control resource set; monitor a second search space of the secondcontrol resource set, wherein the monitoring the second search spacecomprises rate-matching second downlink control channel resources of thesecond control resource set for the second search space independently ofthe first control resource set; and communicate with a base stationbased at least in part on control information identified as a result ofthe monitoring of the first search space or the monitoring of the secondsearch space.
 16. The apparatus of claim 15, wherein the instructionsare further executable by the processor to cause the apparatus to:identify first locations for a first set of reference signals associatedwith the first control resource set, wherein the monitoring the firstsearch space comprises rate matching the first downlink control channelresources around the first locations.
 17. The apparatus of claim 16,wherein the instructions are further executable by the processor tocause the apparatus to: identify second locations for a second set ofreference signals associated with the second control resource set,wherein the monitoring the second search space comprises rate matchingthe second downlink control channel resources around the secondlocations.
 18. The apparatus of claim 17, wherein the first locationscoincide with the second locations within the resources of the firstcontrol resource set that overlap with the resources of the secondcontrol resource set.
 19. The apparatus of claim 17, wherein the firstlocations are non-coincident with the second locations within theresources of the first control resource set that overlap with theresources of the second control resource set.
 20. The apparatus of claim19, wherein the instructions to monitor the first search space areexecutable by the processor to cause the apparatus to: rate matching thefirst downlink control channel resources to the second locations withinthe resources of the first control resource set that overlap with theresources of the second control resource set.
 21. The apparatus of claim20, wherein the rate matching the first downlink control channelresources to the second locations is based at least in part on a type ofthe first control resource set and a type of the second control resourceset.
 22. The apparatus of claim 16, wherein the instructions to monitorthe first search space are executable by the processor to cause theapparatus to: demodulate one or more downlink control channel candidatesof the first search space within the resources of the first controlresource set that overlap with the resources of the second controlresource set based at least in part on the first set of referencesignals.
 23. The apparatus of claim 15, wherein the instructions arefurther executable by the processor to cause the apparatus to: determinethat at least one reference signal associated with the first controlresource set is in a portion of resources that overlap with the secondcontrol resource set based at least in part on a type of the firstcontrol resource set and a type of the second control resource set. 24.An apparatus for wireless communication, comprising: a processor; memoryin electronic communication with the processor; and instructions storedin the memory and executable by the processor to cause the apparatus to:identify a first control resource set configured for downlink controlinformation for the UE, the first control resource set having firstlocations for a first set of reference signals; identify a secondcontrol resource set, wherein resources of the first control resourceset at least partially overlap with resources of the second controlresource set, and wherein second locations for a second set of referencesignals of the second control resource set are non-coincident with thefirst locations within the resources of the first control resource setthat overlap with the resources of the second control resource set;monitor a first search space of the first control resource set, whereinthe monitoring the first search space comprises rate matching firstdownlink control channel resources of the first control resource setaround the first locations and the second locations within the resourcesof the first control resource set that overlap with the resources of thesecond control resource set; and communicate with a base station basedat least in part on control information identified as a result of themonitoring the first search space.
 25. The apparatus of claim 24,wherein the instructions are further executable by the processor tocause the apparatus to: demodulate one or more downlink control channelcandidates of the first search space within the resources of the firstcontrol resource set that overlap with the resources of the secondcontrol resource set based at least in part on the first set ofreference signals, wherein the communicating with the base station isbased at least in part on the demodulating.
 26. The apparatus of claim24, wherein the instructions are further executable by the processor tocause the apparatus to: determine that at least one reference signalassociated with the first control resource set is in a portion ofresources that overlap with the second control resource set based atleast in part on a type of the first control resource set and a type ofthe second control resource set.
 27. The apparatus of claim 26, whereinthe monitoring the first search space comprises spatially processing theresources of the first control resource set that overlap with theresources of the second control resource set based at least in part onthe first set of reference signals.
 28. The apparatus of claim 24,wherein the instructions are further executable by the processor tocause the apparatus to: identify at least one physical channeltransmitted on at least a portion of the first control resource set,wherein a downlink control channel is rate matched around the at leastone physical channel.